I never have liked reversing harnesses, I've see one or two problems resulting from them. I suppose if you get a good quality product it will last a lifetime, but I'd feel more secure with a larger receiver, and the elevator servos on seperate channels. That way you can individually adjust endpoints after you've test flown the plane to remove any roll coupling with elevator (other than stalling, that is). The down side is that you of course need a radio system that will support mixing, and a big enough receiver.

Andy