One thing I've noticed about powerpoint's is that I don't think anyone makes the old style LP/78 flip version. They make an LP/LP version, a single sided LP version, and a single sided 78 version; but, not the old style LP/78 version. The old style holders, as well as the old style LP/78 version, are available from
www.thevoiceofmusic.com.
I've also found the quality of these cartridges to be all over the place. Some work great and others will grind a record with just a single playing. I've ruined a few polystyrene 45's by just a single playing with an inferior power point cartridge and I've seen these bad cartridges change the color of the record grooves as it played.
I use caution when replacing any needle or cartridge by playing a few worthless records that I care little about, just in case there is a problem.