I have the one like PP has on 1saleaday but with the cylinder and wedge pads and stuff. It does come in handy. I do like it for the most part. I would love to get some more pads for it. Biggest down fall, you have to keep a hold of the trigger for it to work, doesn't have an on switch. This does get tiring on your arms. Also if you are using it on something, then stop for even a minute, the pad gets soaked and it really doesn't work any more. You have to switch the pads or clean and dry the one you are using. I have gotten to where I line everything up I need to do in the area so I don't have to stop. But even then, after a bit it gets soaked so you have to change the pads. I was barely able to finish my kitchen cabinets before I'd have needed to change pads. Using it for windows was worthless because you had to unplug it to go from one to the other, allowing the pad to get soaked. It also didn't do as well on the tub as I hoped it would do (and the whole reason I got one of these things) but it does help immensely.
Bottom line is, it does come in handy, more often than I would have ever thought. I do like it and I'm glad I have it. It's a bit inconvenient at times, and a bit expensive, but still worth it. I'd recommend getting extra pads for it if you can, esp those for the cylinder attachment.