I try and get Samsung or Micron Factory Originals when possible.

Memory is like laptops... theres really only a handful of actual manufacturers, and Samsung and Micron are two of them. alot of the big OEMs, Dell etc. rebrand samsung often. They're very reliable when you get em 'straight from the factory'

I did some work with a memory wholesaler and the sales guys were always happy to get Micron and Samsung cause they're good chips at a low price.

as stated above Crucial gets alot of really good memory (including Micron) but it's hit or miss as far as whats in stock. I just ordered 4 GB of DDR2/667 for about a $100.