Yeah, it looks like I bought the smart harness from magic marine, wasn't very impressed.

Initially I set it up like I would a rock climbing harness, relatively loose leg straps with plenty of tension around the waist, but it would ride up awkwardly when on trapeze, shoulder straps pulled it up. I then tightened the leg straps to prevent this but when sitting in they would tighten unbelievably around my upper legs leaving bruises after a days sailing.

I used it twice before swapping with my brothers skiff nappy. He shouldn't have too much trouble with it because he'd be sitting more upright when on the gunwhale (12ft skiff) as opposed to having feet at bum height on a cat. The nappy is much better but I haven't fine tuned it yet.

Having said all this, I haven't tried to fine tune the smart harness off the water. Will probably be forced to when my brother starts racing again and wants to have his harness back.