I like all three of them a lot. But I like Articuno a tiny bit more, though...
This is probably because Articuno was the first legendary Pokemon that I ever had a card of, and that I ever knew of.
The first time I saw it in the first opening of the anime, along with Zapdos, and the other time when I opened one of my first Pokemon card booster packs ever, I instantly stuck to admiring its elegance and beauty.
It's just beautiful, and it has a very cute cry in the Anime.:cheeky: