I used one with my last labour. I couldn't recommend one enough!!!! Wish I had of tried them with my previous labours. A couple of times I though that it wasn't really doing anything, so I turned it off "OMG" I then realised how much it actually was doing. Mine was just a cheap ($25) unit I bought off ebay. My only advice is to have a play with it beforehand, so you have an idea what it will feel like and how to control it properly, because it isn't something you want to learn in the moment.