I have used Logitech 2S on my iMac for 6years and recently just upgraded to Logitech 3S. Hated the magic mouse due to it being weird size and not ergonomic. Both 2S and 3S performed similarly. The only annoyance on 2S is the placement of the side scroll wheel that is too close to the thumb, causing my thumb to accidentally nudged the wheel all the time. This has been corrected in the 3S. Have been using the 3S for the past 3 months and it has been great. Logitech have even changed the scroll wheel to become fully metal, which i feel is great compared to previous one which is coated with rubber (blardy rubber will melt and attract dust overtime). Battery is ok, quite lasting. Usually will charge it once a month sekaligus together with my keyboard and trackpad. My logitech 2S has been holding its charge relatively well despite using it for 6 years.

P/S: in case u are wondering why there's a hole on the logitech 2S mouse, it's because the thumb button was stuck after many years of usage, and i need to tebuk a lubang to make it unstuck, if not the whole mouse will jammed up and become unusable. After doing that, the mouse becomes normal and functional again. But I decided to upgrade to 3S because my 2S now look horrible although still usable.
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