Three things on Scary Sharp:
1. I think it's brilliant. I used to use a Norton double-sided oilstone (for thirty years!!!), and never got good results. The first time I tried SS I could dry shave with the plane iron, and the learning curve wasn't there - I just followed the instructions carefully. And you can still put a camber on a plane iron with a guide - I like the Eclipse sort (much copied) best of all, but it's not suitable for everything, notably useless for skewed blades of any type. I have an aluminium Axminster guide for those, on which I've marked skew angles, which makes it easy and fast to set up.
2. A big reason for 'suddenly' getting good results was that I was properly flattening the backs of everything I sharpened, probably for the first time ever. I hadn't realised how crucial it is. Backs need to be VERY flat and VERY smooth at the edge (doesn't matter much further back). It's a rarely-needed task, but it does have to be done carefully. I think the need for a flat back is the biggest inhibitor to getting old edge tools working well - rust pits the surface and destroys the edge-forming ability, and you have to flatten past the deepest pits near the edge (which takes bloomin' ages). I've got two glass plates now. The smaller one will be dedicated to back-flattening, by having the paper stuck down around the edges.
3. Quality of wet+dry paper varies enormously. I got some from Toolstation a while back as it was cheap (or so I thought!) and I was in a hurry. Waste of money - buy cheap, buy twice - it won't stay flat! I buy mostly from Axminster now as (a) they keep finer grades (to 2500 grit), and (b) it's Hermes - good quality stuff. I also use a strong magnet in a thick polythene bag to clean the paper and glass plate between uses.
3a. Work in a good light and get a really good and powerful hand lens. I use an old 50mm SLR camera lens (back to front!), which is about perfect for the job. Keep a cheap filter on the front and the back lens cap, park it upside down and it should stay clean, even if pelted with sawdust. Being able to properly see what I'm doing helped enormously, and above all allows you to see exactly when to change to a finer grit (although you can feel this after a bit of practice).
So, yes, with Scary Sharp you can just grab the stuff and get really good results -- I did! But you must follow the process properly and the cheapest Wet+Dry will probably disappoint.
E.