I have owned the following:
2007 chevy Tahoe
2009 F150 with 5.4 liter
2000 F250 Powerstroke
2010 Cadillac Escalade
2012 F150 with Ecoboost engine
The best towing vehicle of the 5 has actually been the F150 with the Ecoboost engine, pulls my X2 effortlessly.
The 5.4 Liter with Ford worked well and I put 150k on the truck with no issues, was short on power- I had the exact same experience with my Tahoe, reliable but it struggled with hills etc...
The F250, well it towed great, sold it when I realized how well the 2012 F150 towed.
Escalade towed pretty well, the 6.2 liter engine was a beast.
I put 100k plus on every vehicle I have owned, no real problems with any of them. I am not a biased brand guy, I buy what I like, I almost bought a tundra this last go around, but I just like the F150 a little better. Two of my buddies have tundras and they have been great trucks for them.
good luck, there are a lot of good options out there right now.