Rota is a decent rim company for the money. I would also look to get 16's since I think 17's on a teg are a little too big.
What mods do you have to the WRX? We installed a turbo timer, TurboXS turbo back exhaust and uppipe to my buddies 04. Let me tell you that getting to that uppipe was a PITA.
I would keep your GSR as stock as possible since it is a daily driver...maybe put a subtle body kit on it and lower it a little with some H&R OE Sport springs.
Oh and welcome to HAN :wave: