Need help searching for the best GM SUV

[mad max]

I'm looking for a new Yukon/Denali/Tahoe and am trying to find out which one is the most beefy. I like to option of towing my 10,000 boat. I like the option of driving down a sandy beach. I've been weighing the differences between the Yukon SLT2, Yukon Denali and the Tahoe LTZ. Any more helpful information would be much appreciated.
So far it appears that the Yukon SLT2 can come with almost everything except the ac seats and 400HP motor, and has the best mileage at 14 city.
The Denali has the big motor but only available with AWD - not so good in deep sand, and 12 mpg city.
The Tahoe LTZ might have everything ( 400hp motor and 4WD and 14 mpg city) except the auto-ride suspension.

Have I got this right? Any other important differences?