PSP question

Good day, I decided to take a psp for myself, but I have not quite figured out the console versions yet.
I decided to take the SONY PSP 2008 Piano Black and I don’t understand ... This turns out to be a Slim and Lite version with 64 RAM? Just as I understood the psp 2000+ versions, these are slims and they have 64 MB of RAM. But suddenly I'm wrong.
It's just that on some sites I met the characteristics and there it was written, they say, memory 32.
Give advice who is in the subject of the guys, I really want to buy it.