i had the same dilemma for 4months, i wanted to get 530i originally 2004-2005 but rwd, alota people say 530xi doesnt feel as great drive/control wise thats why i was looking at just rwd. but living in canada xdrive is a good thing to have. i made a choice of going with 2005 x5 3.0i. just because power is not a big factor for my needs, mind you 3.0i is smooth and faster than most v6 SUVS out there. the nice thing about 5series is that its the new style and has lotsa new technology in it like idrive, and nicer finish. I drove xdrive 530 and it kinda felt weird, i always say if its a car it has to be fun to drive and the xdrive takes the fun part out of it. And for a SUV x5 is the best in my opinion. I love my truck, smooth, enough power, beautiful on ramps and cornering, and better than most 4x4s out there, ive been dealing new n used trucks for past 4 years and bimmers are my favs. Mind you 4.4 and 3.0 go for similar price now days, i decided on 3.0 just for maintenance and better reputation. i got premium pack with montana, parktronic (pretty useless), new 18" wishbone spokes from 4.4, and cold weather package (heated steerin is sik), just missin the panoramic. i was shocked to see savings on gas compare to cherokees even though its premium. im heavy footed and all city at 15.5l/100km. p.s. 2004+ x5s have new xdrive systems that are great.