If you weight your knee hard you will eventually highside. By weighting the knee you unweight the rear tire,,or take the weight off the bike and unload the shock right at the worst time. Except for some extreme situations, uphill corners,Tremblant and Calabogie,if you are wearing out sliders at Shannonville or Cayuga you are putting too much weight on your knee.Those tracks have really short corners and do not wear sliders. Heat is what wears out sliders. Just look at a cheap set coming off Bogie. There is a 3+ inch stream of melted-rehardened plastic trailing off.
There is no slider made by any leather company that will last,,FACT. There are made to wear. Injection moulded plastic is soft and some have honecombe cores.Once you hit the honeycombe you're done.
At Calabogie every factory made slider used by the pro's at CSBK a few years ago barely lasted a session. That's right a session. Michael Barnes was taping spare sliders inside the fairing. Then he bought a set of ******' and they lasted two full days.
Shannonville and Cayuga your sliders should last forever!
If your legs hurt your bike is probably not set up right or you're working way too hard or both.