I use it.
The transaction fee is reasonable (around 2.75%), which is good considering that I didn't have to sign up for an ongoing service contract or purchase equipment like you do if you get swipe service through the bank. It's actually a very nice deal.
I like that I can create my own services listings and prices, then just check them off to add to the invoice automatically. I attach the reader to my tablet in the studio, which also has a bluetooth keyboard. Makes the whole process look very official when I flip the tablet over for them to sign digitally. I've used it on my phone as well.
Great service, highly recommended.