Corsair is the best, but I have Kingston. Keep in mind though, if you ever want to upgrade your memory (meaning get a new stick), I know at least with Kingston that you can't mix and match.
Rant: The fact that you can't mix and match with Kingston sucks, because the place I got my computer from (online) jipped me by only giving me 256mb instead of 512, but you can only report any problems like that within 7 days. I have a 3 year warranty, but I can only report problems within 7 days.

And I realized they jip me in like a month. By the way, never buy from ibuypower.com