I thought it was reasonably well done although it's a shame that Rory and Amy were given very little to do until near the end. The guest stars really were the best part of the production. The flying fish were pretty cool but I didn't quite get their importance in the story. That part seemed kind of tacked on to be honest.
Of course there were some timey-wimey bits that appeared out of synch with previous stories, such as the Doctor being able to totally re-arrange someone's personal timeline. If he's been able to do this, why not go back in time and, I don't know, fix it so big bad guys like Davros have the puppies they secretly wanted? I suppose it falls under the category of "some things can be changed, others can't" rule, but allowing the younger and older selves to meet definitely flies in the face of previous "rules".
Yes, it's Doctor Who....and rules are made to be broken, but still....
Anyways, it's not the best Who episode, but far from the worst.
