Or, the OP got what he was looking for and is sitting back watching the fireworks.
When it looks like a troll, walks like a troll, quacks like a troll... It's a troll.
Simple answer is an F150 with a 12,500lb tow capacity, you will never be happy with towing 9900+ over much distance. On the other hand an F250 with a 12,500lb tow capacity, you will be very happy towing 9900+ anywhere and everywhere unless you have an apoplexy any time the engine exceeds 2000RPM. Then, get the diesel.
The difference is duty cycle.