It's definitely just the "1600 upgrade kits" that don't do well on wavemakers. I have >7 year old unmodified Maxijets running on a wavemaker that are still going like the Energizer bunny, apart from maybe having replaced the impellers (since they only last a few years before cracking or breaking off the little plastic bits).
And for what it's worth the water movement effect was wicked. If you're OK with replacing the upgrade kit on a regular basis (it's not like they are super expensive) you may have the last laugh. I tried all manners of glues, epoxies, acrylic weldon, titanium shims inside the shaft, etc. - to repair the busted holder arm but nothing I did lasted longer than a couple weeks. I gave up on the idea after a while but maybe you can have better luck than I did.
