Reasons to watch
First of all, George Hamilton's Playboy-esque bachelor pad. (At about 0:35) It's incredible. I've never seen a better one on film. The set designers went all out. Unfortunately it's not on screen long enough.
Second is the hilariously overproduced "disco" and "rock" music (we get only a few seconds of each, sadly.) Third is Conway's vee-neck tee showing through his sheer polyester turtleneck sweater. So tacky and goofy looking!
And to the earlier poster who said Janssen can't act, I say wrong-o; he was the only one I found truly convincing, dramatically speaking. (Besides Kirk, of course, who can out act anyone else in his sleep. This role barely required him to shift into second.)