Watched Wrath of Khan for the first time last night. I have to say that I'm not a trekkie (although I liked TNG) and this was my first encounter with TOS. And... it's ok. Everybody on the internet say that this is the best thing ever, but I'm not so sure.
But before that, let's talk about the good stuff. Firstly, I really liked the acting, Shatner and Montalbán are great, the rest are ok and everything works, you quickly know who is who and who likes who. Moreover, I drooled during the departure from the station sequence - the expository shots are great and really satisfy my "I need to see some sci-fi ship close-ups" needs. I also liked the more "we're in a submarine and we're partially blind" way of fighting.
However... Well, it aged a bit. When it comes to said fighting it's a bit clumsy and really dated, especially the encounter when they both basically disable each other. I know it's the '80s, I'm just looking at it from the current perspective. Also, I really hate myself for saying this, but I find something missing in the pacing. Again, it was filmed 30 years ago and things were done differently (I still whine when I watch Dirty Harry walking into a police station in a scene that takes something like 10 seconds and would now be probably cut to 2 seconds or not shown at all). Film-makers now have a tendency to cramp too much action into every minute, limiting the story, the acting opportunities etc. and I completely agree that this is a bad thing. However, you just feel that the pace could be a bit quicker. Another thing - although I love Shatner's I'm old-I fell young arc, I can't help but notice that there were some somewhat clumsy moments in the story, for example, when they are almost killed by the two officers and are saved, deus-ex machina style, because suddenly the mind controlled guys stop being mind controlled.
All in all... I still lack something in the style of Battlestar Galactica or Space Above and Beyond, a flick with reasonable acting and a believable or semi-believable setting, with some good starship action. Wrath of Khan is nice, I enjoyed it, but it just lack something. Maybe Star Trek in general lacks something for me, as I recently rewatched the first two seasons of TNG and almost always had this feeling of "I probably want something else" (although I know the first the seasons are generally viewed as terrible).
