I upgraded to the G3 as part of a larger upgrade project. I have had good results
I have not had a belt slip, but I had not had a the G2 belt slip either, as the motor always slipped before the belt did.
So I am unsure if I really needed the belt. But I have been driving the upgraded belt a lot more aggressively without issue. ( I don’t know if a g2 could have taken it or not)
Here is a link to a post I made about a damaged belt that shows its size.