In short, I don't think I understand myself that well with or without typology, but I think typology has been more of a help than a hindrance.
I think both the Enneagram and MBTI/Jung have helped raise my level of self-awareness, especially the Enneagram because it focuses so much on a person's core flaws and blind spots. When I was reading about Nines, I got that stunned, punched-in-the-gut feeling that happens when I discover something about myself that I already knew deep down but didn't want to admit.
However, on occasion I've caught myself misusing typology. There's sometimes a temptation to simply accept my types as The Answers about who I am instead of using it as a framework to help guide further introspection. Also, since I was a kid I've been prone to trying to fit archetypes (for the most part unconsciously) and I think in the past I've focused too much on the archetypal and stereotypical aspects of my personality type, especially when they were appealing to me (for example, INFP as healer, soul-searcher, or withdrawn artist, and 9w1/974 as pixieish dreamer) instead of viewing type as mainly a rough model of how part of a person's mind works and what drives their behavior.
(But, I wouldn't have fully recognized the extent of my tendency to merge with ideas of people and types if it weren't for the e9 description, so obviously typology can illuminate or obscure someone's true tendencies from themselves, depending on how it is used.)