IS very impressive in feel and operation.
You can tilt the top over another 20% making it much more comfortable in the hand. it feels so good really and the best thing is I have it connected to the laptop through bluetooth and through dongle on the studio pc. I just click a switch on top and then i'm controlling the next device. operating two computers with the one is brilliant. BUT! I can program buttons on the trackball to do a list of over 15 operations. I programmed two of them to copy and paste, that is awesome as well, when you tilt the wheel left or right you move the track like a jog wheel. There other buttons on it you can program too i may program one of them to "cut" and see how that works. When i come out of cakewalk those buttons go back to normal operation. The programmed buttons are specific to whatever program your using. It's worth it to have supm like this in the studio, just thought I'd pass it on.
1Love

I thought about getting MX Ergo but I could not justify it because my M570 Trackball still works great for music production. Although I am still considering it.

I use the Kensington Orbit Scroll Ring. I highly recommend it.

The USB connection on this thing is for charging only.
So you need two free USB slots to use it and recharge.
 
It has built-in non user-replaceable rechargeable batteries.
When they go, it's gone.
The older one with the blue ball uses one normal replaceable battery (which lasts ages).
 
And the models previous to that had a cord.
I can see why a mouse with a cord is a drag, but a static trackball?
 
I'd also be interested how robust the switches are. On the older one,
the switch under the wheel would begin to fail quite soon.
 

I had looked at these, but is not clear if it has hyper-fast scrolling (like the M705). With the amount of documents I work I cannot lose that functionality (I cannot find if that ergo scroll wheel is heavy brass and can be unlocked?). Scrolling 20 pages a second is priceless compared to a clicker wheel that might get you a page every 3 seconds, and give you carpel tunnel as an added bonus. Just how fast can the ergo scroll a document?

The other downside for me is the resolution seems incredibly low considering a trackball is static and should get finer control (although the ball is smaller). My M705 is 3x higher, and some cheap corded mice have up/down buttons for resolution to drive it all the way to 4000dpi (that feature is nice for detail work when you need to drive to pixel precision). The only trackball I ever used years ago was the size of a cue ball and I *thought* the resolution was better (may be faulty memory too).

Hi. I have a Logitech M570 Trackball, and cannot get used to it.
I also have a vertical nouse that I can't get to grips with.
Still using a conventional mouse.
All the best.

@mettelus, the wheel is light aluminium and clicks permanently like with the M570.
The button switches between dongles, allowing you to use it with two computers.
It does not unlock the wheel to spin freely as you mention. Would be cool.
 
Incidentally, there is no way of knowing what the state of charge is before it's time to recharge.

Zargg
Hi. I have a Logitech M570 Trackball, and cannot get used to it.

I made the effort because I work in crowded trains whilst commuting.
It is also an advantage on cluttered desks like mine.
And flicking the cursor from one side of a page to the other is faster than repeatedly moving and lifting the mouse on a pad until you are there.
 
But it clearly is an oddity for most, otherwise there'd be far more being sold.
That said, my Mum is 84 and couldn't imagine using anything else!

Thanks for that feedback. The other thing that would suffice is if Logitech allowed a button to temporarily assign scroll functionality to the ball, but I am not sure if it can be done. It is odd for me that Logitech doesn't consider large documents in its functionality.

The big advantage of a track ball for me would be the static position on the desk. With an ultrawide monitor there is a fine line with resolution and windows pointer speed so I literally pick up and reposition my mouse often enough to notice. The mouse is horizontally challenged for cursor motion, but a trackball would be vertically challenged for scrolling. For folks with 3 side-by-side extended monitors, the horizontal challenge would be worse, I think.

Had a look at it, but not impressed. Not usable in XP or W7 according to specs. 
 
I'm satisfied with my Logitec Trackman Marble, better value for money and a smaller footprint. 
Been using one of them for over a decade, and needed to get a replacement as the left-click 
button worn out. Still same design with a few extra buttons. I can live with that :) 
Fairly easy to maintain, you just rip out the ball and remove whatever dust and fat that has gathered in there,
and plonk it back in. No mouse disease or repetitive strain injuries here.