While I've had moderate success with the Citadel line of paints that Game Workshop hawks at every opportunity, I've been looking to get some paints that were a little easier on the wallet. I saw "Tamiya Color"'s fat little pots sitting next to the Citadel ones every time I go in, so I figure, what the hell, why not give 'em a try?
So I bought three- Flat Red, Copper, and Flat White. I figured that even if the paints aren't quite as good as the Citadel range, at least I was saving a little money, and besides, I could probably make it work.
The copper was, by far, the best paint I'd bought. It goes on great, thins really well, and plays well with my Citadel paints. I actually liked it so much that I changed my mind on how to paint my dwarf's cannon and painted it a bold copper instead of a much more sedated Chainmail. I've started using the copper more or less everywhere that I can make an excuse for it, I like it that much.
The Flat Red was much worse, however. The pigment was thin and sparse, and covered my models exceptionally poorly, to the point where it was almost unusable. It took multiple applications to even approach an acceptable level, and even on the last coat it still took it upon itself to flow and move, creating clumps of bright red next to patches of dull red.
The Flat White had the same problems. It seemed grainy and didn't mix well with water at all, turning an unusual shade when mixed. It actually seemed sort of greenish, which is odd, considering it looked extremely white out of the pot. I think it would be an alright color to mix with other colors, but it's still an abysmal performance regardless.
My verdict? Pass for the regular colors, but feel free to use their metallics. All the metallics I've used have worked well, mixed well, and looked fairly good on the tabletop.