Apache looks good. I'm building the same model now-my third of the AM Mustang series. I'll get one right one of these days. I've been using them to practice various techniques; I'm going to paint my Apache in a NMF--my first foray with Alclad II.
I've tried both airbrushing and pastels on these kits. My exhaust's edges come out too hard. I just don't have the technique down, and feel like my control is not where it needs to be to risk wrecking my model at that late stage in the game. Also, making the exhaust look the same on both sides of the fuselage is a crapshoot for me.
I recently bought the Tamiya master weathering pastels. They're like little makeup kits. Although I made the mistake of applying the pastel-exhaust over a clear coat (sprayed on for decal-application), they nevertheless worked very well. I had much better control over the finished product (AM's P-51A). I'd post a pic, but I'm not at home now to take a photo).
I've got three more of these AM Mustangs to practice on before I dig in to the higher-end section of my model stash. Good luck with your Apache. Looking forward to seeing how it turns out!