Though I hate to see old threads revived, this one isn't REAL old, so here goes...
The issue isn't pulling the F-250, it is stopping it. I let my electric trailer brakes go too long without adjusting them and then got caught in stop and go traffic through Seattle. The motorhome brakes got stinky and faded, but it happened in 35 mph traffic and did not result in any trauma.
IMHO, you should have excellent trailer brakes on both axles with that much weight behind you.
'04 National TropiCal T350
Behind the coach: