Lin,
Yeah, mine are collecting dust in the bay! They not only don't work they are great for pinching fingers.
704,
Didn't know about those, probably much better than sawing PVC but, as I remember, it was not much of a job. What I actually used was some green fibrous stuff that is probably for foundation drain systems. It is not as heavy as PVC but PVC is not hard to cut with a coarse toothed saw.