Ok, stright up, I know absolutely nothing about these things. What is the difference betweent a PCM card, a Korg MCR-03 RAM card, and a ROM card? How much do they cost?
Any help will be greatly appreciated. Thanx.

PCM cards have new samples on them. So if you just have that M1 piano sound, a pcm might have a real acoustic piano sample...or new sax,drums, strings, that you would not find on the original M1. The "EX" on synths give you more samples too. The Rom or data cards give you new patches, combis, and performances using the new samples found on the PCM card if it is a PCM/Data card set. Ram cards are like a floppy disk for the PC. It is a blank data card and allows you to store new patches, combis, performances. It does not store new samples like PCM cards. You would have a hard time finding any PCM/data cards so the price would vary.