Whichever feels best to you is what I'd do, the 502 appears to be larger, physically. There is also the Logitech 700 series..that would be something to look at but I think they are a bit more pricey.
Hey guys,
I want to buy a new gaming mouse and I can't decide between the Logitech g302 and g502. I mainly play league of legends, but from time to time I also play shooters and other genres. I have claw type grip and I also have quite big hands.

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