I bought two 1 GB sticks to upgrade my Macbook from 1 to 2 GB, and the price was better compared to other sites. I was looking to be able to run games and more applications at once without using hard drive swap memory so much.
I have had good experience with the Kingston brand. The plastic packaging on the RAM was nice and the shipping packaging was sufficient.
I had to refer to my MB's user manual to install the memory, which was pretty easy. The only trouble I had was that I had to press really hard to insert the new RAM, but this was only due to the Macbook's slot design.
OS X and Windows XP recognized the new memory immediately with no trouble (I dual boot). I would definitely buy from here again! The shipping was very fast too.