The plastic clovers started shearing very early on in our testing. So we quit on those early. The glued end caps entombed the hardware inside the PVC once the clover tore the pipe was no good. So the whole thing quickly became trash. The ones we practice with are duct-taped end caps, then used the conduit strapping in a triangle pattern like someone suggested on here (I'll look for that picture and link it here). That holds up for a while, but the strapping isn't thick enough gage. Maybe if we doubled them up it would stay. But like you said, just dropping them busts em open. The plastic clovers were the easiest to break. That metal flange they made to hold the magnet would work good.
The stress concentration in the folded corners of that plastic will never hold up. But the bolted points tore out also. It's just not a capable material. I originally was worried we would get penalized for breaking these things, but I later convinced myself they were going to be breaking all over the place by design issues within.
http://www.chiefdelphi.com/forums/at...achmentid=2807