I'm looking for advice on a 3 series. I'm new to BMW; 2008 535xi for about 4 months now. Love the car! I am considering buying a 3 series for my son, 2008 or 2009 xi (northeast winters). Other than more HP in the 335xi and its higher cost, what else should I be considering? Is one more reliable than the other? Any other considerations? Sorry, but I also posted on the 3 series forum, too.