I like the cartridge style, as well. I think Pentair and Hayward are pretty equal. Our pool is @17K(?) and with the 4 element Pentair I clean it twice a year, and it still doesn't register restriction on the gauge.
The newest ATCs are nicer inside. Vinyl/composite flooring, and the cabinets, while still aluminum, have a much more residential look, and new pulls/handles. My wife was not digging the previous race trailer look at all LOL
You can call it bullshit all you want if I have bruised your Toyopet pride, but everything I typed is 100% factual. I have owned dozens upon dozens of vehicles for both business and personal use, and that 4-Skin was one of the worst, hands down. I don't drink anyone's Kool Aid. Junk is junk.
Issues? Suspension creaking issue from day one that turned out to be shock mounts, after wasting numerous trips to the dealer I found/fixed it myself. A/C Failure and recall requiring dash removal that they botched. A horrendous brake bias design issue that made it a very real danger to drive...