Hello Phil, I use both Domino machines, the 500 and the 700, but I certainly wouldn't be without a morticing machine. And if I could only have one I'd stick with the morticer.
Where the Dominos really score is when you've designed your furniture from the ground up around Domino tenon sizes, and when the quality and precision of your other machinery is sufficiently high that you can guarantee absolutely square and accurate components. Tick both of those boxes and Domino construction can clip hours off your build times.
However, I still find plenty of situations where Dominos are either very much a second best or just won't work at all. Here are a few examples,
-Dominos offer very little flexibility in terms of mortice width. There are plenty of depth options and plenty of thickness options, but for width it's basically 13mm plus the diameter of the drill bit...and that's it! Sure, there are workarounds involving making up your own loose tenons and drilling overlapping mortices, but that's a lot of faff which largely removes the productivity benefit which was the main reason you got a Domino in the first place! So if your components work well with a 21mm wide x 8mm thick tenon then terrific, but if you absolutely need a 50mm wide rail and a 35mm wide tenon for example, then there are better and stronger solutions than a Domino.
-Dominos can't cut haunches. Maybe that's a problem, maybe it isn't, depends on what you make. Personally I make plenty of occasional tables and console tables where I'm trying to get the leg cross section as small as possible, often around 30mm. A strong and secure mortice and tenon in a leg like that needs the additional glue surface that a haunch will provide. Indeed sometimes I've pushed the design even further and need "interleaved" and off set tenons, again I'd really struggle to achieve this kind of construction with a Domino. So if you're trying to push your furniture designs to stand apart from the High Street then you'll often be disappointed with the Domino's lack of flexibility, the perfect Domino item of furniture can sometimes end up looking a bit "samey", a bit mainstream.
-Obviously doesn't apply to you, but I've known a hobbyists get a Domino because they thought it would guarantee them accurate frames. Unfortunately they were working with indifferent table saws and planers, so that their components were often fractionally off from square, had traces of snipe, or weren't bang on accurate to length. The problem in these circumstances is that a Domino references 100% off the components, so if they're inaccurate then the whole job is inaccurate. Using traditional M&T's you get into the rhythm of scribing the joint to achieve perfection, and if you have anything less than a superb cross cut facility then there's still plenty to be said for that traditional method.
-If you make chairs or furniture with curved components it's easier to knock together a fixture that'll hold a curved piece in a morticer than it is to use a Domino.
Like I said, I've invested in both Domino machines and use them regularly, they're superb bits of kit. But the wider the range of furniture you make then the more likely that they won't be a silver bullet solution for all your jointing needs.
Good luck!
