Because I load so many bikes on and off the Kendon, I had to learn to do it by myself, and riding up the ramp was the only way. So I took a sheet of 3/4 inch plywood, and bolted it under the ramp using the using two mounting holes in the middle. The board is wide enough that I can walk the bike up in first gear using the friction zone. I know the Kendon company does not want people to do that for liability reasons, but since I work alone, it's my only course of action and I accept all risks. I've gotten pretty good at it. The only bikes I have issues with are bikes with fairings. When coming up the ramp, the fairings block the riders view of the rails and wheel chock. I like to have someone stand in the front and use hand signals to guide me up. Backing the bikes off the trailer is so much easier. I leave the bike in first and use the clutch to control the rate of descent. With the plywood in place the ramp cannot be bolted under the rear, so I just bungee it between the bikes. Never had a problem.
One design flaw that irritates me is the placement of the brake lights on the rear side of the fenders. Bikes with floor board are always scraping the inside of the fender. I've broken two sets of lights. Luckily they can be bought cheap at Pep Boys, and even cheaper from on line parts stores.
Truth be told, if I wasn't limited by space and needed a fold up trailer, I would have bought a drop rear.