Fantastic quality of stuff, I built a guitar with their Jackson neck and Strat body. The waiting was a bit quicker than they estimated, something like 4 weeks for the neck and 2 for the body IIRC. The only real drawback is the cost you get lumbered with for importing into the UK, but that's nothing to do with Warmoth - just something to keep in mind when working out how much it will be, as you're gonna have to pay 17.5% VAT when customs get hold of it.
As for setting it up, you will need a luthier to do that anyway - I still need to get a nut cut and setup on mine, as although Warmoth installed the precut nut and frets, you still need it done to your taste by a luthier or yourself.
For painting, it's not that hard really to get a professional finish, there's the ebook we've got on Shredaholic (the Paint Your Own Guitar ad on the main page on the top right) that shows you how to get a factory finish pretty well, but there are free resources available on it too. You could go down this route with spray cans, or you could get it Warmoth finished. I did mine with cans as the finish is acrylic so doesn't stop the wood from ageing like poly does.