Ok, so when I saw this headline I was POSITIVE the OP was trolling. However, peterh seems to be asking the question in good faith so I'm answering in good faith.
GAP makes a hell of a rifle. If you're buying your first custom rifle and haven't had that much time behind precision rigs, then I'd make a list of everything you want and look out for any close matches to come up in the for sale section. You'll save a few hundred bucks trying out your first rig, and once you shoot it awhile, you'll learn what you want and what you don't want. The chances that you just happen to choose the components of a rifle that perfectly suit you in your first rifle are slim to none. Between the differences in stocks, triggers, actions, barrel lengths, barrel contours, twist, caliber, and scope magnification, reticles, knobs, illum, etc etc etc is something you can really only learn by shooting a lot and seeing what you're best with. If you're going to drop some serious cash, then save a few bucks by reading about all the excellent smiths (Gradous, Spartan, APA, SAC, LA Precision, Tac Ops, Accurate Ordnance, etc etc) and look for a good used rifle in the caliber and general specs that you want. Once you tweak your understanding of what will work and what won't, then order your dream gun from the smith of your choice. That's my unsolicited advice.