I'm starting to think I might have to move these books up in my reading plan. I didn't realize people had enjoyed these that much.
I bought the first book years ago, and only read it a couple of months ago. It left such an impression, coupled with wanting more "mature" TOS in the wake of the already-classic Vanguard, that I had to find the rest.
I read all remaining five books in the span of about a week...