Interesting discussion. Something I found out long ago, the only difference between an F250 and the F350(except Dually) is one leaf spring. Everything else is identical. I had an F350 Dually and while I was waiting for service I took a walk out to the new trucks and compared the two, they were side by side so that made it easy. Both were the same configuration, 4x4, long beds, supercabs. I counted leaves and the 350 had one more than the 250, all the rest of the components were the same, including the axles, both happened to have the same gear ratios. Both were also power strokes, 6.0 turbo eaters. What it boils down to in this case is that sticker on the door. You pay a lot extra for 4 leaf spring leaves and a sticker going 3/4 to 1 ton, unless it's a dually. I wish I could afford a dedicated TV, I would snap up another F350 Dually diesel in a moment. Great tow vehicle and not that bad a daily driver, but a maintenance ***** when used as a DD. Be prepared to dish out $100 every 5K miles for an oil change. I hitched up to my New Yorker HT and it pulled like there was nothing back there. Had to keep looking back to make sure it was still there.
As for the F150's, they have some of the strongest frames in the 1/2T market. Hydro formed tubes, not channels like the Superduty I had. My F150 has a stronger frame than my Dually did. What it does boil down to, and was pretty much pointed out very well is the axle rates. Mine has a 4050# rear axle, front is 3450#. That adds up to 7500#. GVWR is 7100#, with the 3:15 gears it equates to a GCWR of 14,500#. So provided you can keep the TW in the payload range, you can pull up to a 7000# trailer. Trailers I am looking at fall into the 7000# GVWR. I may go a little over the Payload rating, I feel it is way under rated at 1470# for a RWD 5.5' truck. Heck I loaded nearly 2000# into a 1979 Ford LTD wagon and it hauled and stopped just fine, due to the magic of air shocks. The rear axle is not much different than what is on my F150, standard 9" axle.
Just to be sure of the numbers though, going to load all the people in and take it to the scales. I have no need to have anything in the bed, not planning to take a lot with us, just clothes, food, and other essentials. No bikes, or other gear. I know by myself I can pull either trailer I am looking at and be way under payload, but add in 4 others, 2 adults and two kids and its going to be a little over by maybe 200-300#, but still within the 7100# GVWR of the truck itself. I pulled my New Yorker HT with it and it felt like it was back there, unlike the Dually, but the EB definitely has the power to pull it. It's about the same weight rating as the TT I am looking into. It just has a lower COG than a TT, which makes for a more stable platform.
So with that said, unless you are going to pull a TT of 7000# gross or lower, don't use the F150 as the TV.
Oh BTW, reason I even popped into this thread, I was doing a search for a Wildwood 30QBSS to find out its TW and other specs and this was the first that popped up, and pretty much answered my question. Yes my F150 can tow it, but it would be over the top of rated specs, so I ruled that trailer out. Looks like the KZ Frontier 2405 is leading the pack. Its ratings are all falling right where I need them to. Its not much longer than my New Yorker and its GVWR is the same with a lighter wet TW.