My dad has had a couple of them! And he always comes home, and says they are painful, and wicked expensive! I don't have one, and I don't ever want one! Sorry that you had to get one!

 I'm glad you decided to change dentist.

 One Saturday I spent 10 hours in the dentist's chair having root canals on almost all of my lower teeth and prepping them for caps, bridges, whatever it was going to take to make my smile look human again. The following Saturday took 8 hours to do the same thing on my upper teeth. Although extremely expensive I have never experienced any undue pain from a root canal other than one in which all the root tissue was not removed in the first procedure. Having my impacted wisdom teeth surgically removed was probably one of the most painful things I've ever experienced, though. Not the removal itself, the following days of recovery were a nightmare!

 I had root canal many years ago.  My dentist recommended me to another dentist.  The process took a while which made me uneasy ... Actually afraid that it might get painful later on.  But it did not. It felt like my tooth was being chiseled inside which felt like torture to my imaginative mind even if there was no pain at all. I had to go back to the dentist after a week to complete the process. 
 
Years later, I had to wear braces.  The tooth that was saved by root canal, was the one chosen to be extracted.  It was an expensive decision.