This is okay stuff, nothing special. The missile is far too advanced compared to Cardassian technology we have seen up until this point, and the fact that B'Elanna spent all this time programming in various probabilities that the missile should know how to react to without Chakotay finding out is completely out there when it comes to suspending disbelief. I'm surprised she didn't program in a probability that the missile would get pulled into the DQ considering everything else she programmed into it.
Then there is the alien first minister who says to Janeway "You would risk your lives to save people you never heard of before two days ago?" Like I've never heard that being said before on Star Trek.
There is some nice stuff towards the end where Janeway evacuates the ship and prepares to sacrifice herself. This helps to make up for how badly she was written in Prototype
They fired at least seven torpedoes in this episode. It seems the rationing is over.