Our company picked up the Yukon and the Acadia at the same time as part of the same deal. There are some kilometer usage issues with the Denali and because I am a lower kilometer driver we switched primary vehicles.
There is no comparing the Acadia and the Denali, as they are two totally different species. I commented to my wife the other day as I jumped in our Minivan for the first time in two weeks or so that it “felt” like a sports car!
THE BADThe Yukon is BIG. Really, Really BIG. (is that sinking in). It is difficult to park in an urban setting. Difficult to manoeuvre in town. Parallel parking and three point turns require substantial forethought. It is a pleasure to drive but more from a D-7 bulldozer perspective than anything else. Body roll is ever present, the ride is utilitarian at best. The gas mileage is horrible. The interior is not attractive (to me) and storage is poorly executed (one huge bin between the two front seats? Seriously?

This is
supposed to be an $80K vehicle?)
THE GOODThe engine is awesome. In the Denali the 6.2 sounds so great. The only drawback would be that stepping on the gas instantly notifies the surrounding two blocks that you “may” be driving aggressively.
The cabin is huge and very, very comfortable, of course with all the accoutrements including Nav and backup camera. When you are on the highway there is no place else to be.
The people and things room cannot be matched outside of a full size extended van. I can fit three adults and three kids in the is vehicle for a long trip and not risk any “He's touching me!” coming out of the back.....why because it's next to impossible. On top of that I have a huge area behind the third row of seats (almost four feet by just over four feet of flat cargo space). Enough to put in an unfolded wheelchair, an unfolded walker, and bags, and a cooler....it just keeps swallowing up the cargo. With the third row up on the Acadia you are lucky to have 1 foot by 4 foot usable floorspace in the back.
The Black on Black plus the chrome 20's make this vehicle look good

However I did get ribbed by a couple neighbours about quitting my job to become a pimp/drug dealer.

I would consider a vehicle like this as our primary cruising vehicle for the family if we did not have a disabled child. My wife finds it very difficult to hoist the wheelchair into the back of the Denali, indeed it is a large lift. I would probably opt for the Suburban version in all honesty. My buddy has one that I rode in and the interiors were identical save the badges (same IP same guage location same everything) the only thing you really give up is the 6.2 to go to the 6.0. I don't think that is worth the $4K premium on the Denali.
So I don't know how long I will have the beast but I will enjoy my time with this vehicle....until the next one. I'l get some pictures when it stops flippin' raining!