I was wondering what's the difference between CF card I or II or III? I've seen a 4GB Kingston 60x CF I cheaper than a 2GB Lexar CF II card. Is Kingston a good brand? Will it work well with DSLR?
The CFII are thicker than CFI. They need a special slot to fit in, so if your camera only takes CFI you won't be able to use CFII cards. I believe that you can use a CFI in a CFII slot, since the pins are the same, just the physical size of the card is different.
Most, if not all, current CF type II cards are really miniaturized disk drives. Flash memory CF cards are all type I these days.
Chucko might have added that the microdrives are not nearly as durable as the flash memory cards. As a rule, a CF I card will last a long time. A CF II card should be treated gently.