In another Shark Bite-related thread, NYplumma says "Remember, if you're using them on copper pipe, take the plastic insert out."

The instruction sheet for installing the product says the tube support liner "may" be removed for copper and CPVC.

I replaced a mixer valve last weekend and used Shark Bite for the new joints. I have copper pipes, everything is in place and there are no leaks, but I didn't remove the inserts. The wall is still open. Should I go back and remove the inserts and if so, what would be the reason for doing so?

Thanks as always for your help and advice,
Lisa