a) dont base ur judgement on commonality (if there is such a term)
always get what U want. If you had 250k to spend on a car and liked porsches do u think u would opt for a 427 (if they ever went into production) over a GT3 because their were too many on the road? i think not.
B) make ur own decisions.
never let other people persuade u into buying a car. Go to a dealership and test drive the ones you have narrowed it down to.
c) make sure u can afford it
never buy a car that u cannot afford COMFORTABLY. Just because a car is within ur price range doesnt mean you can afford to keep it. Insurance is the biggest factor and from memory you are young and insurance UNDER UR NAME will not be cheap. Then theres fuel, maintenance (turbo cars are high maintenance). 3RD PARTY should NOT be an option.
d) dont drive a car u cant handle
Looking in ur profile ur only 17... my advise to u is BUY A GTS not a GTST. Learn to drive that properly for 2 years THEN buy a GTST especially if ur not going to insure it fully.