Just upgraded from my trusty g602 to the g604. Buttons aren't nearly as clicky and tactile as the g602, but the damn scroll wheel is phenomenal, I can't get enough of it.
Logitech G602 Wireless Gaming Mouse | eBay
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1Piece Wireless Mouse USB Receiver for Logitech G602 New | eBay
Logitech G602 Gaming Mouse Review: Fast and Furious
What type of computer mouse is more comfortable for someone with arthritis or carpal tunnel: regular mouse with a scroll wheel, optical mouse, or trackball? - Quora