I have the forward WIP wing vest Neo. Pretty similar to the impact vest you have but the hook is removeable, takes about 5 sec and it's never come off accidently. I'd say if you are racing and really loading up the wing it would not be as good as the impact vest as the webbing is a fair bit thinner so the load spread into your back isn't as good as a proper harness etc.
www.forward-wip.com/produit/wing-neo-vest-50n/