Speaking only for me, A Piece of the Action is fun, but it's the Star Trek characters playing dress up. There's not a lot there to connect it to the overall continuity...which is fine, don't get me wrong. Every episode/adventure doesn't have to feed into the universe to be enjoyable. We've just gotten through all three seasons of TOS on BD and the ONLY episode the BF fell asleep through-twice-was Piece of the Action. I had no interest in watching it three times in a week, so I stopped a fourth viewing. (And since it doesn't mean anything down the road, what's the point?) As for Trek IV, it is the most accessible of all the movies. You don't need to know a whole lot to understand what's going on and a majority of the movie takes place in present-day Earth. I'd guess that's why it's the most popular. I agree with you on the movie itself, though: I don't think it's very good and certainly not my favorite of the series. It's Star Trek does Greenpeace and tends to be very preachy...topical is the word I'm looking for, I think. Trek VI is topical because of the end of the Cold War, the Berlin Wall and those events, but it's no where near the "in your face" level of Trek IV.