For me it boils down to comfort, sytle and general feeling I get while driving the traverse. I had an 2001 MDX which i definitely thought at the time was the best car I had ever owned (had 4 prior cars to the MDX). After 4 years of driving the MDX, picking up a BMW and driving that for 3 years I can truthfully say that I like the Traverse the best.
Reasons I didn't go for a MDX again:
1. I really dislike the new cockpit design. Just too bubbly/hightech looking for my taste. The 2001 version was subtle, easy to use and I really enjoyed the simple styling.
2. Felt like a girl / soccer mom's car. Totally self conscious on that one I'll admit, but it definitely hit's the manhood a bit after a while. The new 2009 MDX is even worse IMHO.
3. Air conditioning system was finicky
4. Wasn't an American Car. Yeah call me silly, but honestly GM / Ford / Crystler are all american icon's and dammit it just makes me mad to see what they are going through. Don't want to go into any politics on it... I just felt good buying GM this time.
5. More expensive to maintain.
6. Had some battery issues, but that can happen to any car. Just left a bad taste in my mouth.
7. Too small for my family of 5 to feel comfortable.
Reasons I bought Traverse over other cars:
1. I personally like the 2009 Traverse styling more than other SUVs. Seems manly and pretty hip for a SUV hybrid. The grill is pretty sweet looking. I do no like the GMC & Saturn versions... but that's just my opinion
2. Drives so darn nice. Nice acceleration, smooth driving, handles turns great and brakes very well. My old MDX was very nice too
3. Super comfortable. Probably the most comfortable cockpit and chairs I've had. Air conditioned seating... very nice on longer drives I might add. Again my old MDX was very comfortable as well.
4. Fits my family to a T. Me, Wife + 3 kids & Dog. Everyone fits in, can get in and out easy and they really like the extra leg room. My MDX was way too small to travel any distance with the full family, especially with luggage.
5. Feels very solid on the road. Great airbag protection
6. 110 AC in the second seat area... great for kids & gaming for long trips.
7. Decent luggage space with all seats up... especially when you consider the amount of leg room and spaciousness inside.
8. Navigation system is easy to use and has a clean interface.
9. Bigger SUVthat feels like a midsize SUV. My wifes Chevy Tahoe feels much bigger even though it's not.
10. It just fits the bill for both commuter and long distance functionality for me. Very pleased.
11. About 17mpg city and was up to 24mpg on a 4 hour road trip the past weekend. I reset the meter when I got on the freeway to see what it came in at.
12. Takes regular unleaded gas... no need for mid/super grade. Waste of money.
What I don't care for when I first got the car:
1. Turn radius is a bit wide. It's not horrible, but the MDX has it beat there for sure.
2. Road noise can be noticable when it's windy. I can't remember how it was on my MDX, but the BMW was pretty quiet. I think I'm just noticing the difference from a sedan, but it's definitely louder.
3. Felt it was a bit plastic on some of the internal trim initially. After checking out a lot of peoples cars since I've had my traverse for about a month, I realize that most cars are like this and it actually holds up a bit better and can be wiped down. My father owns a Toyota Highlander and his is almost trimmed out the same. Back in 2001 the MDX had pretty nice trim... mainly leather all over. I don't know if it's changed or not. It seems like a lot of car models have switched to the plastic for durability.
4. Didn't like that I could not program a destination on the navigation while driving (disabled on most cars now due to laws). "GM Lockpick Gen 5" will solve this though. Can google that if you don't knwo what it is.
5. That my dealership snuck in a 200 deductable on the extra warranty I got for 7 years. I went back and complained (and complained a bit more to the GM) and they changed it to 0 deductable. Yeah the finance guy tried to pull a fast one on me and it was my fault for not catching it at the time of signing, but in the end it worked out. Word of advice... make a deal on a new car at the end of the day to get the best deal, but have them prep it and actually finalize the paperwork in the morning. I was tired and just wanted to go home and eat dinner, so I went too fast and didn't read the fine print in as much detail as I should have.
Hope that gives you some info to help decide.
Cheers!