Limitations for a 2008 Pathfinder w/ V8

I am new to this forum and would greatly appreciate any constructive input regarding my post. Currently towing a 2006 Rockwood Roo 21rs with my 2008 V8 Pathy. It has the load leveling / torsion bar hitch setup but not sure of the brand. Started out with my 2002 Frontier and it was a disaster hence the purchase of the Pathy to replace a dying Honda Odyssey as the new family vehicle / tow meister. Pathy is rated for 7000lbs, current Roo is 4000lb dry. Add a 1000lbs of kayaks, bikes, frozen chickens, people etc. and I still have roughly a ton of breathing room. The torque on the Pathy is more than adequate for this setup and with the anti sway bar towing is almost a non event other than semis periodically blowing by at 75mph. Now to my question / concern. We are looking at shifting to a Roo 25RS/SS. With the two slides instead of one it's heavier plus the extra 4 feet in length. Weight wise I should still have around half a ton breathing room so my real concern is wheelbase. Will sway become a nightmare with the longer trailer footprint or not? Thx for any assist!