People will complain about anything lol. A brand new mouse using a totally fresh sensor with potential to be the most accurate sensor EVER, tunable for surface lift off, not only tunable weight but tunable weight bias front/back/side/side, programmable buttons, and Logitech's epic durability...and people complain about how it looks in pictures or that its middle of the road weight LOL. Keep in mind a 10-15g heavier mouse that is held palm grip will feel lighter then a claw grip mouse that weighs less due to how you are holding it.
Bestbuy 20 minutes from me shows them in stock, might go pick one up today. My trusty G9x will become my backup mouse if it is as good as I hope - and my 9 year old G5 that STILL WORKS FLAWLESSLY will be my "backup backup mouse"