Keep in mind what you use your pistol for when doing the grip.
A really aggressive grip on a competition only gun that will only be worn OWB isn't going to feel so great against the skin for IWB concealed carry.
I stippled one of my Glocks year ago. I also removed material from the underside of the trigger guard where it meets the grip. For me it was a huge difference. Install of trying to hold onto a bar of soap the the pistol was planted in my hand.
I was pretty aggressive with the stippling and...
None of mine have had wear the pin get beat up like that.
Regarding aftermarket parts and sending it to Glock - a Glock employees advised me that with the exception of sights Glock will discard any aftermarket parts on the pistol when they service it. I have spoken with people that have sent...