I have never used any of vallejo paints, but i am wanting to switch to a indoor air brush based primer paint. I think i want to try vallejo's product. I was wondering 2 questions though- 1. does it need to be thinned first? If it does is it alcohol that thins it? 2. I mainly use enamel paints, so would vallejo be a good primer for enamel based paints. Thanks im sure these are newbie questions