Summary: I had used Logitech track balls in the past and though this one might work. Cliking both buttons for scrolling was too much of a hassle. I chose a Logitech wireless Performance mouse MX instead.
Summary: I think that massive positive reviews of this product is a result of ignorance of masses. I have used computers for more than 20 years and most of this time I used trackballs. I am used to scroll wheel on a mouse or trackball therefore its absence in this product makes it barely usable.
Summary: I'm writing this for the sole purpose of informing anyone thinking of converting to this mouse from either the Trackball M570 Wireless or the old sadly missed wired version Trackball. This mouse contrary to what descriptions on amazon and other sites may say, has NO SCROLL function whatsoever. Every page must be scrolled using a browser's scrollbar etc. The software included gives no button programming that allows a workaround for page scrolling.
Summary: I have been using Logitech trackballs since forever. In Oct 2012 I replaced a mouse that came with my new computer (Mac) with a new Logitech Marble. No problems...at first. For about 3 months everything worked as expected. In Dec 2012 the Logitech Marble I had been using for years on my Windows 7 PC started going out, or so I thought. I trashed it and replaced it with...you guessed it...another Logitech Marble. I loved them! Suddenly everything started going wrong.
uncomfortable scroll buttons that depend on software
Cesar R. Romero Perozo, Amazon
1 November 2012
Summary: I don't understand how this mouse can have a high number of positive reviews. It is the most uncomfortable trackball I have ever used (e.g. Kensington Orbit , Kensington Expert , Kensington Slimblade ). Here are some problems: -it doesn't have a scroll wheel, so you have to hold buttons that are placed in a very awkward place (see tiny buttons on pic).
I never give 1-star reviews, but I had to on this product!
Magnanimous "Magnanimous", Amazon
31 May 2012
Summary: I am thoroughly shocked over how many people have had a good experience with this Trackball mouse. I have had really bad carpal tunnel for a few years and I have tried soooo many products to help with the pain. I see a hand specialist now even. This can help to have different movement than with a usual mouse, which is good temporarily. I wonder how many of the positive reviews are from newer users.
Summary: The Logitech Trackman marble has some design flaws. First, the side buttons are too sensitive to pressure. Just limply resting your fingers over the right button can activate it so you have to then left click to close the pop up window. The scroll button is too small and located right next to the large, touchy, right click button so while trying to activate "scroll" I instead also activate the Right click button with my finger because the button for scroll is too small...
Summary: I used a Logitech Trackman Wheel for over two years until the mouse button started misbehaving. The Trackman Wheel was the one with the marble on the left that you move with your thumb. Moving the marble/pointer with my thumb was much better ergonomically than the way you have to move the marble on this newer Trackman Marble.
Summary: Too long buttons in wrong places. Middle finger extends beyond the button, because it is longer than index finger. Thumb is required to do the fast double click, sideways. Programmable small buttons, good; not reachable easily, bad. Long version: Long time user of Logitech products, the last one was the old right handed Logitech Marble Trackball, I was unable to agapt to this model and had to return it.