My Avalanche has proven to be everything that I expected. All of the cargo space is very useful, we can fit our 3 kids in back easily, it gives a very smooth ride, and the gas mileage is better than I had expected (16-17 religiously). The back seat is roomy enough for 3 adults to sit in.
Smooth ride, roomy storage, lots of cargo capabilities, gas mileage.
The cargo area can be tough to clean out after hauling any landscaping mulch, dirt, etc. You have to take out the mat to get it clean. The overhead taillight/back-up light can't be replaced at home (you will see almost none working on the road).