I was listening to one of my regular diet of podcasts in the car the other day (Meeples and Miniatures, episode 65 - http://meeples.wordpress.com/) where Neil was talking about painting figures. There was a discussion about paint and preparation, and one of the comments was that neither he nor his co-presenter would ever use craft paint other than for scenery.
Which got me to thinking... it may not be as good as hobby acrylics (GW, Vallejo, PP, Foundry or whatever), but is it 'good enough' for rank and file? I have certainly used odd colours in the past, and I will admit that I still use craft acrylics to touch up spray undercoats where the can misses undercuts. So I dropped into Hobbycraft on the way home from the office and I picked up five tubes of FolkArt acrylic (http://direct.hobbycraft.co.uk/productdetail.asp?productcatalogue=246194) which were as close as I could match by memory to the colours I'm using for my Imperial Guard.
What I will do is to assemble and undercoat my next squad as usual (a veteran squad of GW Cadians with Pig Iron heads and backpacks) and then paint five using my usual paints and five using the cheap craft paints. Both batches will get a Devlan Mud wash, and then I'll see whether I can tell the difference. And I'll post the pictures so you can compare them too.