Even though i have never taken their course,
Their course really works, you get out of there being able to memorize a quantity of information you never though you would be able to, but the problem is that it demands so MUCH time, so if you got enough time and energy and are really willing to learn it, go for it.
Anyways, here's a link with many memory techniques you can use to improve your memory, i personally did and i must tell you, its amazing, and i think, basically, that Pmemory teaches these techniques but they provide you more tools to learn and master them.
Mind Tools - Memory Techniques and Mnemonics