I'm new to the forum starting today. My situation is similar to VAredRAM's except that I have an '09 Ram 3500HD 4WD SRW pickup. I made an assumption that I'd be able to carry the AF990 w/o any issues...
Towing a trailer with its own brakes makes little difference. When I tow my flat bed with over 2000 lbs and no brakes on the trailer is when I feel the difference in stopping distance. My enclosed trailer at 7000 lbs stops quicker due to its own braking system.