An exciting opener to the season that I really can't deny I enjoy so much purely because we get to see a bunch of our regular cast disguised as Klingons. It's so much fun.
I particularly like how each of them take to the challenge in different ways; Sisko makes for an astoundingly good Klingon and really plays up to the stereotypes of being aggressive and full of vigour. Odo, meanwhile, struggles to break out of his depressed state and doesn't quite fit into the Klingon mould as he's quiet and reserved. And then there's O'Brien who really doesn't succeed at all, despite putting some effort it. Apparently Colm Meaney absolutely hated the prosthetics and was really uncomfortable, and some of that comes across on screen.
In many ways, this episodes gives me a newfound respect for the actors who regularly play Klingons and how easy they make it look. Michael Dorn is the obvious candidate, but JG Hertzler as Martok is absolutely fantastic here (and it's no surprise that he returns later). It seems a little strange that Jadzia doesn't go on the mission given her extensively knowledge of Klingons.
There's also brilliant fun scenes with Dukat and Damar, who is acting more like the character he'll become. This gets the show nicely back on track to dealing with the Dominion as a big threat and patching things up with the Klingons, and it's really successful.