Interesting release! I'm glad to see it's still working to this day. There are so many broken provided clients around on the internet. Just for reference, there are actually many different ways to proceed with getting a client - in order words to a WoW Cataclysm Download.
There are both possibilities for Mini Clients of Cataclysm as well as Full clients. I myself prefer a mini client so I can get right into the game, while leveling anyways. I guess that's a preference on what type of what WoW Cataclysm 4.3.4 Client that is prefered.