I found that CF cards are more expensive than the SD cards so I used a SD/MMC Card to Compact Flash Type II adapter with my MPC500. It works just fine. No problems.
nice, hopefully it holds up over time and no errors occur on the sd card... no odd fragmentation type things.. and no data corruption.
I have heard that some people who have gotten multi card readers on their mpc over time of using SD cards they started getting issues. I dont remember the exact nature of the issues but you may be able to look it up.