Pros: Reliable, cheap, easy to use.
Cons: A way to start presentations would be nice.
We have a lot of academic visitors who give presentations using powerpoint. Many of these events are filmed. We wanted a cost-effective way to have them not be hunched over the laptop as they moved forward with their slides.
After a bit of research, we went with the Kensington, mostly based on price, but subsequently bought another based on its performance.
As you'll see when you look at the product specs, it uses 2.4GHz wireless technology, measures 1.75x0.75x4", and runs on 2xAAA batteries.
Like most other presentation devices, it has a USB device inside the top part. By taking this out, the device is effectively switched on. In my experience, the driver software for the clicker loads in well under a minute, although your mileage may vary on this one, depending on your system specifications.
It has very few controls. You can't start your presentations with it. Once you're going, you can go forward, backwards, or switch to a blank screen (using the stop button). The fourth (of 4) buttons, is a red laser. It's small, but works pretty well.
The device itself is very ergonomic-feeling, with a slight rubberized texture on the bottom. It feels substantial, and not cheap, without weighing a ton, and it's not so small that it's hard to find if you put it down.
The effective distance for use is claimed at 60 feet. I think that's a bit of an exaggeration, but for distances of less than 30 or so feet, this has been unbeatable. No complaints from any of our users. It's been very reliable.