Just did a new blog post about how to get information about photo storage and framing for conservation from the Image Permanence Institute: photo storage guidelines
They sell Bainbridge Artcare MatBoard which is the same thing we sell. As far as I know it is the best. Right now Bainbridge has exclusive rights to manufacture products with the Artcare process which helps actively protect artwork. The best other manufactures can do is offer products that wont harm your artwork and perhaps buffer them.
Good read, thanks Mark. As a part-time archivist, I cannot stress enough the importance of acid-free materials. There's really no point in using expensive papers if your print will be devoured by acid within a few year.