Concerning the recoil springs..
I have the "old" springs,do not change every 100 rounds..
The original recommendation was every 500,then was changed to 250..
Just me,but I have not had any problems with any of the pups that I have shot-plus I bought extra Recoil springs before they changed them!!
My grip screws have not worked out,I always make sure they are "just snug" I feel no other reason to get in there anyways..
Shoot a little and carry a lot..
YMMV