I buy and sell rvs, and the rv Im speaking of will maintain its value for several years. Once they get to a certain point they stay there. The 3/4 truck will ride every bit as good as an SUV that is equipped to pull a TT.
I would not worry about the resale , especially in Texas where there is a strong market for the smaller 29-31 ft fivers. And a truck is the real vehicle of choice in Texas, as you know.
If you keep the Mazda, you gotten then buy a dolly or trailer to pull it with and some states require braking systems on both. That COST MONEY.