Just traded my wife's 4.4 X5 with sport package for an '03 MDX Touring. The X5 is a tight, stiff ride with firm seats, excellent handling and impresses with a test drive. However, with time, one realizes it's very tough to drive, especially with one hand, and every crease in the road throws it (and your passengers) around. It's tough to turn at slow speeds and has a touchy accelerator, which makes it difficult to drive in city traffic. This rig requires complete attention at all times and frankly, given the paucity of space behind the second row seats and handling characteristics, you might as well buy a 540 wagon, especially given it's astronomical price new (we bought hers used with 9k). The navi was not user friendly and we didn't need it anyway, so opted not to order it on '03 MDX.
Conversely, I'm extremely impressed with the handling of the '03 MDX and also how nimble it it is. It tracks the road well without being pulled by every crease and rut and is great in the twisties. It has a much smoother ride on the freeway, and the third row seat is awesome for our 9 & 5 year old boys. The Bose system, while tossed under the bus by others on this site, is more than adequate and much better than the Bimmer's. Unlike the X5, this rig gets better with every drive, and nothing out there can touch it for it's overall attributes. You'd be nuts to buy anything else. Didn't think the RES was very good, so will be adding an aftermarket one, with much help from this site (thanks boys). BTW, drove an '02 MDX before we bought the Bimmer, and the "03 appears to be a little quicker and nimbler than the '02. Wow...just read this to myself and will be requesting a fat commission check from Acura!
Dunno yet. Haven't driven the MDX in the snow, but I can't imagine it having any problems. My only experience with snow is in the mountain passes, and the X5 was surprisingly adequate, even with 285 19's (yes, you read that right) on the X5 with sport package. The MDX tires have to be better than the X5's, just based on common sense, and the 4WD system should be awesome. Perhaps someone else is more qualified on this subject, but the lack of complaints on this board from folks with nasty winters probably speaks volumes.