We have a few family pools that all run on pentair equipment and while we typically run our pumps for 6 to 7 years, we replace unconditionally the IC40 SWCG cells every 3 years or when warranty runs out.
Same for the pentair cartridge filters, outer case and media. This saves us time and maintenance plus we pickup new warranty for another 3 years on the replaced parts.
Just swapped out perfectly working slightly over 3 years IC40s for IC60s. Price from local wholesale outfit was only usd 40 more for the IC60 and it fits into union without any mods.
Tested each of the IC40s in a bucket before disconnect and they foam up the water nicely showing the cells still generate, cells are also totally free of any deposits.