The seat stays where the Zefal clamps go are already heli taped so hopefully it should be okay and as it's jammed on top of the RRP ProGuard it's absolutely solid and can't sag towards the tyre. I think the Maestro rear triangle on the Giant lends itself to this kind of set up as non of it moves independently behind the linkages so there are no issues with changing clearances.I used to have the zefal rear, great guard and easily adjusted but it has a tendency to really rub your paint work and I got a very annoying duck quacking kind of noise from it when hitting the gnarly stuff lol.