Haha, I actually went with one of each.

They're even going to be in the same machine, although the Seagate just arrived yesterday evening, and I was too tired to install it last night. I'll let you know soon which I like more. According to the latest reviews, the Seagate is ever so slightly faster than the 6400AAKS, though I don't expect to be able to tell any difference between the two.
edit: BTW, I've never had a Seagate drive fail, and I first started preferring them about 15 years ago. Then again, in 27 years of owning computers, I've only ever had one HD failure. (As I go look for a piece of wood to knock on.

)