I had an ECV, and Moxibustion, neither worked, even though the Midwife doing the Moxibustion said it was 100% percent for her so far! Also tried handstands in the swimming pool, the torch up the fanjo, frozen peas on top, cleaning floors...nothing worked. But I think she had been breech forever, we only found out at 37 weeks, had ECV at 38 - very late really. She was wedged up right into my ribs, not a hope really.
Had an elec c sect, although it was brought forward because of high BP. The ECV was uncomfortable, mostly the friction and pressure was painful but it didn't last - I used the breathing techniques I was learning for my home water birth!
As far as I remember, they inject you with something to loosen the muscles, then turn by basically pushing and manipulating round. The baby is monitored before and after, as are you. the Injection can make you feel a bit strange, but its not unpleasant - make your heart race I think, can't really remember. The I had to stay in for a bit, relaxing in a private room, on delivery suite, just in case you go into labour, as someone above said. They tried twice with me, and booked us in for another a few days later (although annoyingly, changed their minds about that when we had been there for 2 hours). We kept a labour bag with us just in case. I think I could take some paracetamol or something after for the soreness, but it only really lasted during the procedure.
The C section was ok, we were told a couple of days before that I did have a choice of really pushing (hehe) for a natural birth if I wanted to, but I just didn't feel that the consultant was behind it, felt I would have ended up with a emergency c sect, which I didn't want.
I do think our baby was very stubborn though! She still is now...and we named her Maggie, as she 'wasn't for turning' 
HTH - I think the thing is, it's different for everyone. In the end I just couldn't stand all the what ifs - if the baby turns then this, if she doesn't then this...I just agreed to C section and then could just prepare for having a baby rather than worrying about how she was going to arrive. hen I spent three days relaxing in our heated birthing pool!
Really hope it works out for you, hope my waffling helped a bit!