Well, all cordless mice will need a battery; some have rechargeables in there.
I'm currently using the Logitech MX1000 laser mouse, and it's been terrific. Not really in the same price range, but the prices on them have dropped fairly nicely since I bought mine.
The big differences I've seen in optical mice is the distance you can be to the surface of the mouse pad or table, and still track properly. With cheaper optical mice, they would have a hard time with surfaces that exhibited any irregularity. The Logitech one actually works while hovering above the surface of the paper, out of physical contact. I also used it from two rooms away with no problem (you might ask how I would do that- I had a CCTV camera pointed at the monitor and I was viewing it through the TV monitor
Battery life with the Li rechargeables have been no problem at all, it goes a good long time before it needs to be put into it's charging cradle. It also has battery status LEDs to give you warning well in advance when it's getting low.
It has all the extra buttons mentioned for auxiliary functions, which is definitely handy.
The only drawback is the size of the receiver, which acts as the charging cradle as well. Works fine for desktop applications, but not too good for my notebook; just doesn't stash well in my bag.
I got a Microsoft notebook mouse, which has a storage bay on the bottom of the mouse for the tiny USB receiver, which works nicely, except it doesn't have as many buttons. No problems tracking though, and the battery life of the single AA is such that it's no pain to swap every now and then.
Only thing I don't like about it is that it has a rubberized surface that extends down to the edge of the bottom, so when I use it on soft surfaces, it ends up dragging. Have to use it on a rigid surface as a result- no such requirement on the Logitech.