I found Sarepo GT300+ mouse for a good price and its ips looks ok (100) but 20G looks kinda low is it good or not?

thank you20G is low huh, you know how much muscle force is required to hit 20G?
here is list of good mouse sensors, yours is listed aswell
https://thegamingsetup.com/gaming-mouse/buying-guides/flawless-mouse-sensor-list