In reply to CurlyStevo:
The lower trigger bit (the bit that levers up and down to let it slide) seems pretty flimsy, but since you can't slide the thing up and down on the old quarks anyway, you could just leave it off when bolting the rest on.
The main bit should then be pretty solid - maybe not as much as Grivel's metal trigrest, but more ergonomic and fine for a downward load.
I've not used them in anger yet, mind, and maybe they wouldn't be so good for lots of torquing, but I reckon they'd cope with a bit.