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I bought this trackball because I'm a really messy person and have trouble keeping clutter away from my desk. This means I often had to sweep things aside just to have space to move my mouse. This came to my rescue and as long as I have space to support the footprint, I can use my computer unhindered.
Trackballs don't seem to be nearly as popular as I feel they should be, and this affects availability. After many searches, the Kensington Orbit seemed to be the most affordable trackball with a scroll wheel (a very important feature for me).
Upon opening the box, my first thought was that it was much larger than I anticipated. Though I admit I hadn't given it much thought and if it was much smaller it would be far less useable. The build quality is good, as solid as you'd want something like this to be (I wouldn't try using it for hammerthrow practice). The finish is fairly standard for most mice and keyboards, it's that lightly textured plastic that has become so ubiquitous in the world of computing. It's not pretty... But it's not exactly ugly either, and I think it's probably more comfortable in use than a completely smooth finish would be. The ball itself is a nice blue colour and has a metallic finish, which I think is to aid the optical tracking but has the added benefit of looking quite pleasant. The scroll wheel has evenly spaced ribs all the way around and is finished in a very slightly rubberized plastic in a lighter shad than the rest of the trackball.
Installation is as simple as finding a spare USB socket. In fact, the most difficult part is probably trying to get the USB lead plugged in (it's never the right way up first time!)
The ball moves very smoothly and the cursor is fast but accurate. The scroll wheel is very comfortable to use and becomes second nature in no time at all. It scrolls continuously with no clicks and is very responsive, but it does sometimes seem to miss a beat.
The only problem with this trackball is that it can get a bit sluggish quite quickly if it's used frequently. Dirt builds up on the contact points and introduces friction. They're easily cleaned but there are small ball bearings that act as rollers between the ball and the body and care must be taken not to dislodge them. I accidentally popped one out while cleaning and it caused the tracking to veer to one side. I replaced it with a ball bearing of the same size but the original was not metal but may have been plastic or some sort of jewel and the replacement was not able to perform to the standard of the original.
This is a great trackball; it's a bit on the expensive side, but performs well. Being careful when cleaning under the ball should enable a long life. My only criticism is that no spare bearings were provided, especially given how easy it is to lose one.