I had seen these machines around but didn't want to spend a heap of money on something I wasn't sure would actually work. Then it came on special at Farmers and I took the plunge. I should have done this ages ago and saved thousands on salon treatments!
I used this on my arms, it isn't painful at all and results started showing within 4 weeks, I was using it weekly. Now I'm using in on my arms every 3 weeks (or when i remember) and just zapping the few stubborn hairs that need it. It states not to use this in the summer when you may be tanned, but I started right in the middle of January with tanned skin and it worked fine. I'm naturally pale with dark hair. Also use this on other areas of my body, including my face, and there's no pain at all.
Overall, it is fast and easy to use and the powercord is super long, which is a must, and while the results may be slightly slower than professional salon treatments, the price and convenience of it totally outweigh this one small con.