BMW 325ix Install

Call me crazy, but i'm 13 and already planning a car audio install. Anyway, my parents might be giving me an old BMW 325ix for almost free. My plans are to put in a new alternator and replace the old worn-out battery with a yellowtop or something. My question is, what brand of subwoofers would give me bang for the buck and look pretty cool too? I looked at JL stuff and it looks like it's got boom but its pretty boring to look at. Do not say the word Audiobahn to me, my cousin filled a car with Audiobahn stuff and blew it in like 1 week. For the non-subs, there are 2 5 1/4s in the front kick panels and 2 in the rear deck. Another concern is where to locate the subs, I plan to start with 2 in a ported box and then work my way up. Any suggestions will be greatly appreciated.

Oh and PS: Is MA Audio any good?