All the mice (or mouses) that I have at home are optical, and none of them have mousepads.
I've found that they work fine without the pads, with them they keep going off the edge which is ******* annoying. However, as the Stick said, they underside of the mouse does tend to get kinda dirty without a mousepad.
But meh, just scrape the botton off after a while and continue
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