Which should I go for? The 01s are cheaper but are there any changes in anything from the 01 to 02 to 03? I was looking for a 4.4i but realized it was too heavy on gas and this was going to only be my daily driver. Well I was just wondering what can go wrong with an 01 x5 3.0i or 4.4i with around 50-60k miles. Which is more reliable the 3.0 or 4.4? What are some things I should look out for? Any suggestions?

Thanks