The only thing I really dislike is the premise. I could see the humans wanting a cloak for their ships, and I guess hopping to another universe full of naive suckers would be easier than stealing it from folks that will kill you on sight. But we know the evil empire has cloaks. That's just dumb.
I don't find the rest too bad. It was a decent Ferengi episode, and a stupid-fun romp in the mirror universe. I never really liked the μniverse in DS9 anyways, but the silly Ferengi stuff made it bearable.