How can you be talking about having a lifetime's worth of student loans and buying an $80K Porsche as a gift in the same thread?
Anyway, not my business... but unless you're Donald Trump buying your girlfriend a car after just over a year of being together sounds like a bit much. Even The Donald would be wary of setting too high of a precedent from the get-go.
But what do I know, I'm older than you are and I couldn't even afford a Porsche Cayman for myself.
BTW... nice pics in your sig. The black E90 and the red Mini make a great couple.