Zapdos has a better design, and is a fairly useful Pokémon in its own right.
Zapdos is the only Kanto legendary that I like. I voted on it.
Fan of Generations I, III and V
Thundurus is more useful than Zapdos to me. Even if Zapdos can possibly take a hit better, Thundurus's ability gives it PRIORITY on ALL Status moves. This means no matter what it's getting at least one Nasty Plot in before being attacked. Also, Thundurus is a lot faster in comparison as well (Base 111 Speed compare to Zapdos's Base 100 Speed). Also I like the idea of a Raijin better than a Thunderbird anyways.
Anime Characters Claimed: Mighty, Shirobon, Shout (Bomberman Jetters)
I like both a lot, but I think Thundurus is a bit better, he`s a freaking genie! Too bad he doesn`t grant wishes.
They also both got my vote. I like Zapdos' design more and he has always been one of my favourite Legendaries. However, having used Thundurus I cannot deny his own usefulness and so they both deserve my vote.
Starters of choice.
Claimed Volcarona on 03/04/12.