IMO out of the box you don't need to touch anything. Just play with it until it fails (as no matter what everything will succumb to parts failure due to friction, stress, etc. just because parts are moving and wear out and whatnot). It's just a matter of "when" they'll fail. ie. An American built car might fail after 100K Km's while an Asian import might fail after 400K Km's they both fail eventually but one usually sooner than the other (however you sometimes get those one in a million cars that don't fail for a long time, ie. some Aftermath Krakens (cheap chinaclone) might last for 100K+ BB's) and even then some TM's might fail after 2000 BB's.
Anyways, just play with it for a season maybe a season and a half and then figure out exactly what you want from your gun and target your upgrades accordingly (if you require it). I'm a proponent of leaving things stock unless you need the extra power, accuracy, ROF, etc. since it can be a finicky, frustrating, and potentially expensive process.
Now as for buying that over something else. I'd really wait for your AV to go through (after you get your info taken down by a verifier it will usually take 1-2 weeks after they've submitted it for the admins to activate your AV status with usual updates being weekly). At least once you have your AV you have a larger variety to choose from. Maybe the G&G does the trick for you or maybe you find something full metal that catches your eye and buy that. Basically look everywhere you can before buying.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE