I have always compared CTR/endurance to hunters/jumpers--both have similar elements (distance riding vs jumping over fences), but the way one is done does not often resemble the other.
I personally have only ridden in 1 CTR, a 2-day 50. It was an absolutely miserable experience as I was riding a friend's seasoned, competitive endurance horse and he and I both thought the relatively-slow required pace was silly. However, I think it would be a fantastic place for a greenie - horse or rider - to learn about the basics of distance riding. If you aren't interested in winning, the sometimes-odd things you can be judged on don't matter. Just do it for the learning experience.
I know several people who love CTRs and don't care for the "loonies" in endurance riding. Each sport has its own appeal.
I would love to try an ATCHA event, just out of curiosity, but the closest one is something like 3 hours away.