I need advice, which car would be the better choice!? Which one would you choose?

They're all great cars but it comes down to personal preference. I personally would get a 3 series. If you were happy with your 2003, then I would get another BMW. The Audi, in my opinion, looks a bit cleaner and laid back. I would test drive both and see which one you like more. I have heard that Audi's have some electrical problems, though. My friend has a 2004 A4 and puts a lot of money into electrical repairs. My dad has a BMW and it is pretty reliable so that shouldn't be a problem for the BMW. Another really good car for the price is a 3rd generation Acura TL. My brother has one and it is pretty nice, and a lot quicker than the Audi and BMW. So I would definitely check that out too. Good luck on whatever you choose to buy.