I have a Logitech G502, and previously had a G700 wireless. loved them both, super configurable, comfortable and have had excellent customer care from logitech in the past. only gripe with the G502 is the wire, after coming from wireless its a bigger pain in the ass than I expected!
I own a Mionix Naos 8200, and it is probably the mouse I've ever owned. Lovely ergonmics. But if you play a rhythm game called Osu! (which I do) you might notice that the sensor has a little bit of drift. Meaning it moves the cursor a little bit more downwards than upwards when moving the mouse around without lifting it. This only a very marginal amount that isn't notecieable in other games but it is noticeable in longer (5+ minute) maps in Osu! But that's simply because you can't lift off the mouse while playing in standard mode.