http://www.keystoneforums.com/forums...ad.php?t=34556
Plenty of discussion here on almost the same trailer. And I'm sure there are many other threads on the subject as well.
My take, you tow with whatever you feel safe with. But I will add that you are most likely looking at something DRW.
I tow about 3000 lbs. less than you with a SRW and payload is almost used up. Just a starting point for you to consider.
RMc