I have 1 of them but found that the 1 I have from Jaycar is easier to work with as you don't need to worry about which hole to put it in, it has a "length gauge" and you can do more than 1 wire at a time. They're a great tool to have.
They are a great tool just be mindful that you use the correct hole, if you use one too small they can nick the conductors which will cause the wires to break easily with a bit of flex.
I have used both, the first one I have used for well over 25 years and I thought it was the best stripper to use as long as you set up the correct hole size, else as others have pointed out, you can damage the conductors. It was only last year that I changed to the second type, that I changed my opinion, it is far easier to use, does not damage the conductors, except where the wire is so thin and cheap, the conductors break from the pulling action.