I have been buying my RAM from
Datamem since 1997 and have been very happy with their prices and service. Of the dozens of modules I've purchased, only one was bad and they advance shipped the replacement at no cost to me. I just installed a 512MB stick from them into my mother's new Mac Mini, and it worked flawlessly. Hope that helps. In summary, they are not the absolute lowest priced place, but they really stand behind their product.