Trigs,
It may help to understand the OEM business relationship a little. My own personal experience is in computer manufacturing, but I know from conversations with woodworking equipment resellers that many things in the machine tools industry are similar.
First off, there is no such thing as "Chiwanese quality." I've absolutely no doubt there are factories cheerfully selling the most ghastly old rubbish via Alibaba or eBay or some similar route (I'm not singling those two out), but a lot of engineering factories can produce good quality stuff as well as rubbish, if they have a commercial incentive to do so.
So how is what you see on sale here (retail) chosen for you? At the bottom end of the business is the small volume retailer. They'll contact the factory, possibly completely by remote communications - emails, Skype calls, etc. - or through a buying agent (Chinese national based in China who can be commissioned to find what the retailer wants). They order relatively small batches of products they're offered. The factory *might* customize the paint job, or silk screen a different name on the front, but that's it. Basically you ultimately buy what the factory gives you.
That doesn't mean the worst quality - there will be a price point for all the quality levels they offer, and usually a quite comprehensive mix'n'match range of fittings and styles. The retailer will choose what they want from the list, to make "their" specific product offering. Weeks or months later, depending on the business, a container will land at Felixstowe and some or all of the contents will be on pallets that get road-delivered to the retailer, and so on.
Crucially, the quality control (QC) is in the hands of the factory. If there are problems, well tough. The retailer has bought the whole batch and they've been delivered. The factory has payment in full, returns to the factory are usually quite uneconomic, and the fix for the end user is almost always breaking down a brand new machine (for spare parts), or sending a whole one to the consumer as a replacement. To cover this inefficiency, there will be a quite large mark-up by the retailer on the factory gate (or freight landed) unit costs, and the business can be risky, especially for the first few consignments, when the retailer doesn't know the supplier, and neither party knows the common failure modes of the product in use (because it's a new design). This sort of retailer will probably use a really low price to tempt you, as they have few other alternatives, but crucially they are characterised by selling few units of each item. But a really low price? Ex-factory it's already a low-priced product, so you _can't_ be buying a lot of value for your pounds. There are high-value low-volume exceptions to this, but that tends to be 15,000 quid units bought in batches of five by specialist retailers, who themselves demand a high level of factory post-sales support. It doesn't apply to the 250 quid tablesaw.
Next up, the branded product lines: This may be a decades-old brand name, and the products will be badged and in the livery of that brand (e.g. dark blue for Marples, but I'm only using that name as an illustration, I have no idea how that brand is managed). Apart from the branding, the business relationship with the factory may well be quite similar to the little guys. This is because brands often do quite low volumes on individual items, but they need to be seen to have a broad range. The items will be more expensive, because they carry the costs of brand advertising. The "brand equity" means those retailers (or wholesalers - some sell direct, some don't) will offer better after-sales service, but their sales costs are high (big ads in magazines, sponsorship, sales reps on the road, loaner units, and after-sales support to an extent), so they won't want an uneconomic factory gate price. The actual products will be the cheaper versions in a given price bracket, because of those high sales-channel costs. The buyers may visit or be based in China (or wherever), but beyond the paint, there is little product customization.
Finally the real OEM customers: These people want a longstanding business relationship with the factory, because they see a benefit to both sides. Their deals cover both individual product lines, and may even formally document an overall business relationship. Their products, whilst based on a standard offering from the factory, usually involve customer requested modifications as necessary, for example component substitutions (such as different electrics), to improve safety, performance or reliability, better bearings, subtly different machining of castings, and so on. They also do their own localization, meaning writing their manuals in English (not Chinglish!), and testing to make sure products work as intended and really are safety compliant, not just accepting someone in Shanghai's CE declaration. They'll often have their own reseller chain, and they will do sales training for those resellers.
In their home country (e.g. the UK here), the distributor/retailer will maintain their own engineering team, to oversee quality, before the products are made, and analyse field failures for product improvement. They can do this because they sell in much higher volumes than most of the other players. If you're taking, say, 100 units a year of a certain low-end saw, you take what you're given. If you are doing 2,000 units, you get the right to say, "You used sub-standard bearings; I want these bearings replaced with better ones on the production line, and no, I'm not paying more than we originally agreed, and I want a returns pipeline set up to upgrade the units I'm now expecting to fail!"
Importantly, the manufacturer is learning, too. So someone may request a truly nifty modification to their (ex-factory) design. The factory would like to give it to their other customers too - to keep their loyalty. This is where the company-to-company agreements come in: the big distributor gets exclusivity for a certain length of time on product changes - keeping them on only their brand of products. After a while, typically one or two years, the factory is allowed to put the modification on all their output. I can think of one recent example where a lever was replaced by a handwheel (more ergonomic). That was exclusive to one brand for a year or so, now all that class of product is the same from all the retail brands that use the same factory.
It's not to say that the big players are always offering you superb products -- they have a range, and they want you to 'trade up' to a bigger purchase, so they have a conflicting interest in limiting the value at the bottom end (but they really do need the volume of sales too!), but they have a hand in the engineering of what comes from the factory. They are also much more likely to carry spares, have knowledgeable people on a help line, and so on, because they regard the product as theirs, much more than just something they're buying in and selling on.
Bear in mind too, that none of them want units to fail early. The reputational damage and the support costs arising wipe out profits really quickly (think of recalls in the motor industry). They want customers to feel they got _appropriate_ value from the unit, so they'll buy again. Put too much quality in and you _will_ go bust, as people buy once and never need to come back. Because of this, industrial manufacturers generate profit from their support and service operations (that doesn't happen much in the retail business). For retail operations and their sales channel back to the factory, support is seen as a cost, not a profit generator.
So what about warranty? Is it a measure of quality? The retailers would like you to think that it is, but usually it's a hard-nosed business decision (if it has any actual meaning at all).
Imagine you're a product manager in one of the machine distributors. You have an idea of how many units of the thing you sell will fail over a year. If you haven't, you make an educated guess. The in-warranty costs of those failures hit your profitability. If you allow for them, by ensuring spares and/or replacement units, AND a process(!) are all available, there's a money tied up. If you have a short warranty, people won't buy from you. Then there are legal implications if it's a consumer retail (even thick DIY-ers have rights if they abuse products - the EU says they should!)
So you look at the market, at the quality and pricing of your competitors' products, and the warranties they offer. You talk to the factory about common failure modes and their costs. You talk to your marketing manager about your on-target bonus! You form a view and you make a decision.
That's why you'll see effectively the same thing sold with a range of warranties, not just across the world but even via several companies in the UK. You'll even see the sheds, and certain brands typically found in the sheds, offering 'no quibble' straight swaps - burned out drill for new, for example. Imagine how low the factory gate price was, to enable the retailer to continue to make money on those deals!
None of the above helps your decision as such. There is no right answer.
Are you deciding on the best tool for the job, money no object? Buy Mafell or Festool or Fein or Lamello, (or whoever). Has it got to be the cheapest thing that lasts for a fortnight and doesn't explode in use?
In that case buy... well never mind.
The point is, for anything where there are a lot of choices in the marketplace, which isn't a big (and therefore more expensive) manufacturer brand -- we're talking about Chinese products, after all -- I think it pays to look at the companies selling to you rather than the products. You choose your own product 'mix' quality versus cost, how much you need that warranty, and what that warranty deal actually is*, but the crucial question is how much you trust the people you're dealing with.
Long post - sorry - but it is a complex subject. Hope it was helpful,
E.
*I have a specialised and very expensive stainless steel hot water tank in the house. It turns out the UK manufacturer's 'lifetime guarantee' is so tightly written it's not worth the paper it's printed on. Contacting them with a genuine problem (because of their poor manufacturing quality standards) found them unhelpful and downright rude. I have learned from that and I'll never again buy one of theirs. To me that's a sign of a badly run business, and commercial fools - basically trying to deceive the owner, in their point-of-sales literature and on their web site, into thinking they provide better after-sales support than they do.
Contrast that with, say, Snap-On tools: not inexpensive, but you know they'll stand by their product quality.
