Same here. It's good, it's solid, the acting is great, Barbara Luna is excellently chosen as being the Captain's quiet baddie in the background, the episode is iconic, and there are some great moments about the human condition ("What kind of people are weeeee?", etc), but it is overrated. While even the title confirms "mirror universe", it's still a little narrow and cheesy in scope (possibly even for 1960s standards, the trope was first conceived in the 17th century (Margaret Cavendish) but narrow or not at least TOS was trying to innovate, albeit in a smaller direction). Only 2? Some nitpicks on how they beam into each others' clothes and makeup and hair gel differences also make one smirk. At least there's no attempt at big explanation for those little nuances, the story could easily have been worse.
