You will get lots of varying opinions, but here is mine....

From the 525T, go directly to the X5 3.0. Performance will be very similar. Besides, you will have the smoothness of the I6, just as she is used to. In the '02 and '03, the 3.0 is also better on fuel.

The '02 and '03 are very similar. You've got to go newer to get X Drive, everything prior to that change is pretty minor. I would pay a bit more money and look at an '03 purely from a newness standpoint, but I would also consider an '02 in excellent condition.

I think the sport rides rough, and so decided against it. Ordering again, I wouldn't order sport. I like it on my Z4, but this is not a sports car. Some others wouldn't consider any X5 without sport. Drive it yourself, and let her drive it; then decide. You can always add 18" wheels to the non-sport if that is important to you.

Good luck with your decision.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue