I would say if the wing backs are set at the correct height, then when you are standing up the wings should be around your bottom or marginally higher, that way your can still lean your upper body left to right. At least that's how it works on my boat & I've had no injury, pain or anything in big Hebridean seas!
The only disadvantage to wing backs I have found is the space they take up. I have a double width console with 4 x jockeys & used to be able to walk up the middle of the rib, between the jockeys. But not now! Still well worth having. 120NM round trip to ST-Kilda the wing backs made a huge difference!