They are great, but I'd advise to keep it on from early labour as they work progressively and build up so if you remove it you start from scratch. I was shocked at the relief it gave me after I took it off for a bath. But it wasn't worth putting it back on as I was too far gone for it to benefit me again. I had mine from the maternity ward I think you can book them so you don't pay anything.
The only issue for me was being on a monitor and having to have a button for each in each hand, can get a bit much x