I brought a mouse recently. My second attempt for wireless mouse. My first, a Filand, was terrible. Matchinig by pushing a button was necessary and batteries are running out fast.
This one Ci75m by Kensington is a lot better. I specificially looked for one with wired USB option in case I have flat batteries on the road. It's also flat/small enough for my notebook carrying bag.
It was fairly OK at first when used at home running XP. I took it to office and it behaves sluggishly in wireless mode for some reasons. Luckily I have the wired mode. When used with my MacBook it works perfectly OK.