@holzhamer Pedro, I would have to disagree with you here. AK RC needs to be thinned regardless of what type of spraying you are doing, and in general most paints should be thinned down for the airbrush, save for MRP, or SMS. For general work I thin AK RC down 60/40 (with Mr Hobby Leveling thinner, MLT), for masks I thin it down 75/25 and have gone as low as 80/20. I usually spray at 15 psi and for the more thinned paint I go down to 10-12 psi (indicated, I don't know how accurate my Chinese gauge on my Chinese compressor is). With this ratio I am able to get nice, thin layers of paint and a smooth surface. Just my experience using AK RC for the past 1 1/2 years almost exclusively.
As for metallics, I find the mainline Tamiya/AK have too large metallic pigments. I have used AK Xtreme Metal, and they spray nice, but are enamel and fragile to handling and require a clear coat (chance introducing texture/dulling the finish) to be able to weather (oils) on top of. I switched to Mr Color Super Metallics which are lacquers (my preferred paints), have fine pigments, and don't require any varnish to protect them from masking/handling/weathering. They come quite thin in the bottle but I still thin them down 50/50 or more with Mr Hobby Rapid thinner, MRT, but you could use MLT as well.
Ok, back I go the the Empire of Japan group