Here's a list of excellent resources for mouse enthusiasts, for both learning and shopping.
The real hotspot! - /r/MouseReview/
Switch modding, pcbs, learning resources - https://ents.win
Mouse Switch Master Sheet (by /u/ents) - Mouse Switch Master Sheet
Mousepad Master Sheet (by /u/hoyahoyaa - @hoya_ow on Twitter) - Mousepad Master Sheet
Mouse Modding, Teardowns, Testing and Comparison Videos - https://www.youtube.com/c/Beardedbob
Test controllers and joysticks online - https://gamepad-tester.com
Mouse Shape Tester Megapack by Scout339 - https://www.printables.com/model/113133-mouse-shape-tester-megapack