I can contribute here...I have a 2016 Tundra CrewMax 4x4 with the 5.7 as my company truck. During the summer months I pull a Kawasaki Mule FXT all over the hills and mountains of East Tn. The rest of the year I don't tow. The ride is fair and the towing is sufficient, but not fantastic. I have the split bench model with the fold down armrest. It's only semi comfortable at best. Mileage is TERRIBLE both towing and not. I average about 13mpg not towing and 9-10 towing. Power is pretty good, but doesn't compare to the 6.2.
Prior to getting my Trailboss with the 6.2 in November I had a Titan XD with the Cummins. Pulling the same trailer I pull for work with the XD was completely different. Power and stability. Same thing with the Trailboss. Hands down the TB tows better than the Tundra. Not to mention the interior is far superior. That being said when it came time to get rid of the XD I never even considered a Tundra. It's a great free truck with a gas card and I love it for work, but I wouldn't buy one for personal use. Only point in the win column for the Tundra is the back seat...its huge. Other than that the TB wins every category.