I didn't think I'd like it.
I'm still trying to contemplate what I saw. I liked that it wasn't, at least to me, as ambiguous as a lot of Nolan movies. I was absolutely expecting to walk out of there not really understanding what I saw. That didn't happen.
Though I'm not sure I would want to sit through 3 hours of it again, I'm glad I saw it and thought it was pretty powerful.