We just finished our 1st year towing with a F350 Lariat SWR with the 7.3 gasser. Our 5th wheel has a dry weight of 12,175 lbs. & is almost 35' long. The truck does not struggle towing our rig at all - the 10 speed automatic transmission will downshift when pulling uphill, but that is normal for this truck. All of our axle & payload weights are within specs, and the ride is downright comfy! If you keep your travelling weight less than 14,000 lbs. you should have no issues. And yes, a good hitch will give you an extra margin of safety. We also had to wait almost 7 months before our '22 Ford was delivered, but the wait was worth it! BTW, it does suck gas. You won't be passing too many gas stations when towing. Have fun!
Updated Info:
2021 Alliance 310RL 5th Wheel
2022 F350 Lariat SWR, 7.3 Gas, 4:30 Axle