Our last trailer was a Sunny Brook 267FL with a GVWR of 11300 lbs and a dry weight of 6400 lbs, we towed it many times to Florida from Southern Ontario, we used chevrolet avalanches, had two during the length of time we had the trailer, six years, the avalanche is just the same as your half ton, 5.3, 3.42 rear end, the trailer was a box but the avs towed it fine, you new it was there but that is so for all gas powered trucks. Buy the one you want you will be in no rush to get there so you don't need to worry about pushing the truck to it's limit, see you in Florida in the winter.
"Well that didn't go as expected"
2015 Chev 2500HD Highcountry Duramax
Cedar Creek Silverback 33IK
Donald&Casey cairn terrier
Rest in Peace Mary my darling wife.
Scottish by birth Canadian by time.