I've ordered the 3-ringed (2 large, 1 XL ring), 5', 3/4" tenex Notch rigging sling (130 on ebay, not bad!) however it's "for crotches only", I can't help but think that I'd be just-fine to use it on a spar IF I choked it, I'm picturing using a prusik on one leg that's got a carabiner on it so...