With the trial I had zero pain. The pain post permanent implant wasn't to bad, but they had complications and I was kept in for 4 nights. However if comparing that first time (the first time with the one lead) to the post lead revision (with the 2nd lead threaded) well that was a different story.
Do ring and confirm the trial Gunny, nothing worse than getting yourself all psyched up and it doesn't eventuate.