I will be doing them with my next pregnancy so no experience yet. If you go to the high risk board I know I have seen quite a few posts with others talking about doing them.
I had them done at the doctors office and each week we switched sides. My side would be sore for a day or so, but nothing to bad. Good luck mama! It's totally work it if you can make it to 37 weeks.
Re: 17 P experience?