[Closed] Lubing Pistons - Red rubber grease or Copperslip?

Hi

I want to clean up my brakes and re-lube the pistons in an efort to help my Oro k24's self adjust a bit better, but am not sure whether to use red rubber grease, copperslip or high temperature silicon grease on the pistons as there seems to be allot of conflicting advice out there!

Thanks

Guy