No problems either with NO NAME or original "TechPülley" squares. Best results on small scoots were with spanish made rollers, inexpensive.
Had once to try a set of yellowish/ orange, similar to DrPs squares, but tested its material and found it too soft to apply in my/any scoot.
See link
https://www.kymcoforum.com/index.php?topic=30655.0On bigger scoots, 350 and up I've used only genuine DrPs or TechPülley over last five years. No problems on about twenty/ thirty scoots so far.
Additionally I polish and "dremelfit" ramps AND variator housing to avoid such complications.
See link
https://www.kymcoforum.com/index.php?topic=33615.0I think its also a benefit to use only BANDO or MITSUBOSHI belts in our CVTs plus unglazing clutch pads once in a while.
Your mentioned flipped slider might have been caused by a weak counter pressure spring or sliders too narrow, 0.5mm is enough to topple.