Got my National Pokedex. N and Ghetsis were surprisingly easy to beat (only one of my Pokemon fainted once, and thatwas because I underestimated N's Carracosta and he dealt a Critical Hit to my Lilligant). I used Krookodile, Togekiss, Lilligant, Sawk, Carracosta and Emboar against N. Against Ghetsis, only 4 of them had to fight. And Zekrom was easy to beat. 3 Dragon Claws from my Krookodile were enough, even though Zekrom was 2 levels higher. Zekrom used Giga Impact, but it wasn't all that strong, and then it had to recharge.

And all the legendaries so far have been easy to catch. Didn't even have to inflict a status condition on Reshiram, just two hits, and Ultra Ball and that was it. Are all B/W legendaries so much easier to catch than HG/SS legendaries?

And now I have a level 51 Dragonair, fished as a level 50 Dratini. Not very good in battle yet, but she may improve if/when she evolves into Dragonite.