For Current consumption, Microdrive > CF > SD
and Microdrive is larger in size which cannot suit all film size DC.
In my experience, The PDA limits the read and write speed a lot. The most concern is the battery consumption.
Now, there are SD to CF adapter, we could easily copy file to friends SD card by simply using adapter.
For many low grade DC, the processor unit is very slow, the jerk is on the DC processor but not the card, so does PDA. Hisgh Speed card only shows its performance on high end DC
For, DC the main concern is the speed of recording movie, the unit writing speed will determine the lag time and quality of the movie.
