The (really) good:
1) I paid $5 for this... cheaper than most corded optical mice! Unbelievable it works at all at this price!
2) Works GREAT, on every surface I've tried it. I prefer using a coworker's back, but it would probably work well on anything on your desk. At home, I use it to "drive" a laptop that feeds video to my TV, and an RF/optical mouse is perfect for this non-ideal- surface/not-close-to-PC "work"...
3) The USB receiver docks into the mouse's backside when not in use, which also turns off the power to the mouse completely, thus saving the batteries. VERY slick. For a forgetful laptop user like me, this automatic power switch when I pack up is perfect!
4) Dongle docks smoothly, and eject button works smoothly when you want the dongle back.
5) WORKS CORDED AS WELL when the batteries die. I don't know what the above guy was doing when he said it didn't, because I actually did this FIRST before I even found batteries for it. Maybe having the dongle docked overrides this and shuts down the mouse (???? - I haven't tried...), but without dongle or batteries inserted DEFINITELY works as a corded mouse!
6) Alkaline batteries last weeks and weeks in this with moderate usage. I don't mouse CONSTANTLY, and the mouse has a powersaving mode when you're NOT wiggling it, so constant-surfer/gamers might experience something else. Apparently you can put rechargables in it and use the included retractable cord to charge them, but when the local dollar store sells 16 AAA for a buck, why bother with that?
1) Oddly, when you have the dongle docked, the battery door under your palm feels much looser than when not docked, as if the eject spring is pushing on the battery door. No, you don't generally use the mouse with the dongle docked, but I'm concerned about it banging around in my computer bag, opening itself, and gouging out the components inside... Hasn't happened yet, so stay tuned.
2) What the hell is the "3D functionality"? Nothing I use shows any difference from any other 3-button scroll mouse... Technical marketing lags here...