Towing comfort seems to be very personal - some people are comfortable at the limits of a truck's capacity (some even over, which I would never recommend), some people find that a truck has to work to hard at that point and find it uncomfortable. Proper set-up with WD and sway control makes a big difference. Unfortunately the difference between a boat and a TT/FW is enormous, so how it functions with a boat says little about how a truck will work with a TT/FW.
My thought is that it might work, and you might be ok. But, I'm not sure I'd make the jump without the capacity to replace the truck if absolutely necessary. Locking yourself into a new FW that you can't tow, and being unable to replace the truck, would leave you with nothing but a very large and expensive lawn ornament!