335 to 4.8?????

[PK8]

I'm looking for an '04-06 X5 for my wife, and have somewhat fallen in love with the idea of buying a 4.8. However, my wife believes that a 4.8 for her would be overkill, does not want to have to buy a set of winter wheels/tires, does not want the more expensive upkeep, etc. In other words, she would be pleased as punch with a 3.0, and is very reluctant to consider a 4.8.

I am driving a 335 coupe, and my lease on that car is up in August 2010. I don't know what I will do when my lease is up, but I am now considering getting a 4.8 for her to drive now and for me to drive when my 335 lease is up (and getting my wife something else at that time- maybe a 3 series sedan). I know that none of you can guaranty my happiness with a 4.8 or any other vehicle, but my questions are:

1. For those of you that have gone from a 335, E46 M3 or a similar vehicle to a 4.8, how did you like the change?

2. Would I be better off splitting the baby and getting my wife a 4.4?

Thanks!

PK