Summary: expensive to be first but worth it. 1 month daily use
Pros: Almost perfect trackball. Inconspicuous radio freq. dongle. What the "wireless" trackball should have been all along.
Cons: Occasional screen page ups or downs not quite as many lines as expected though this may be due to the web site encoding I am visiting. Not sure. Either way I can live with it and didn't take off an egg for it.
Excerpt: This puppy stopped my carpal tunnel pain in two days. The mouse does not MOVE - you move the trackball. This way, you can put the mouse on your lap, on the other side of the table you are laying on in exhaustion - anywhere!
Pros: Comfortable Design, Great Features, Works On Any Surface
Summary: I gave it 5 eggs as it absolutely does the job. And I did not think a short break-in period to be worth an egg deduction. Unit arrived within the period specified.
Pros: Really nice replacement for my wired LogitechTrackball.
Cons: Out of the box it was very unresponsive. I thought I was going to have to return it. Changed battery=no help. Changed USB Port=no help. I was about to pack it up and start the return procedure when it started to work correctly. It took 20-30 minutes to 'break-in'.
Pros: Wonderful quality as always from Logitech -- pairs with your exist Logitech Unity usb plug (so you only have one plug filled, even if you have both a wireless keyboard and mouse), and the battery seems to last forever. I have one that's lasted two years now on a single charge.
Summary: I have fairly large hands and do not have a carpel tunnel situation but wanted to try something new. The trackball fits my hand well and, though, it takes a while to get use to using, it's pretty fun!