You wont be disaponted with a GT. They are very durable. A metal gear steering servo should be first on your list to upgrade. The stock servo strips out easily.
Yeah, i found the gt to be an awesome car, but i got the older style about 3 years ago. It was still awesome. Now my gt is upgraded to the newer chassis and a .21 conversion with a hyper 8 port. Its a blast. Anyway, i would reccomend buying some spare e-clips for the hinge pins and crankshaft. Also, a couple spare bearings and screws.