In concept I love Vallejo. They have an amazing line of paints and I think they hand brush well.
I am not wild about airbrushing them. I thin mine with windex. I am apparently the only person who has had luck using them with alcohol (they will gum up, but keep stirring and things get better)
I dearly love Gunze for airbrushing, though I hate the stink.
For clearcoats, I just use the Testors stuff in the rattle can.