Martlet a lot of the thing is to get a nice airbrush, second get a good kit, the other is patience like you said.
I bought 2 P-51 kits at the same time, one Tamiya, the other a Hasegawa P-51 ( because the store had only 1 Tamiya). I'm making the Hasegawa now, probably gonna give it to Steve with our squad logo on it ( Rat Bastards Of America, when we get a logo)
I have to say that the Hasegawa is a few notches down in quality compaired to the Tamiya. In fact Tamiya kits are consistantly better than any other IMO.
The Hasegawa version has flash mold marks all over the plastic, shallow gear bays and less surface detail.
Steve, if I can make this kit good enough, I'm coming over to your house with it
