I've had 3 teeth with root canals. The root canals are expensive, but living with the discomfort is worse. They were not fun, but not nearly as bad as I thought they'd be. I'd put it closer to getting a filling than having a tooth pulled.
I had to have my first one because I had an infected tooth that did not show up on xrays or exams. It developed into a serious infection and it put me in the hospital for almost 2 weeks. I had the root canal shortly thereafter and all was fine.
I'd say, go for it. Just plan on a day or so of discomfort. And also, I still had some temp and pressure sensitivity for several months afterward. Don't expect and instant cure, but it will get better.