WD benefits everyone! In fact, it is the most important part of a properly balanced tow rig.
WD alone will do more to stop sway and improve handling than any sway bar alone could ever manage. It's purpose is not just to keep the back of your truck from settling, which in your case probably doesn't visably happen. It's real purpose to to divide the tongue weight evenly across both front and rear axles. This keeps your front tires firmly in contact with the road, and maintains all the important steering geometry the the manafacturer intended. Keeping those front tires on the road firmly will make the truck handle better, improve steering response, improve braking and keep your headlights out of the trees. It also takes a significant amount of wear off your rear axle and springs, since they are no longer carrying so much weight.
I firmly recommend that all travel trailers have WD hitches AT THE BARE MINIMUM. I would rather see someone tow with a WD hitch and no sway control, than put a sway bar on with no WD hitch. Of course, ideally you should have both WD and sway control, and the best bet for someone like you is the Reese Dual-Cam. This hitch incorporates WD and sway control into one simple setup.
'11 Ford Expedition XL 5.4L (Primary tow vehicle)
'04 Mercury Grand Marquis 4.6L (Backup tow vehicle
'04 Ford Freestar SES 3.9L (another Backup tow vehicle)
'97 Lincoln Mark VIII 32v 4.6L (another Backup tow vehicle)