Join Date: Jul 2001
Location: Near Pittsburgh, Pennsylvania, USA, Earth (PIT)
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Posts: 5,277
A Microdrive will drain the battery somewhat quicker, and it is somewhat more fragile than a flash memory card due to it having moving parts, etc. They certainly do cost less at higher capacities.
Personally, I wouldn't want a single card with that much storage space on it. I'd rather stick with 512MB cards or such (512MB is a fairly sweet spot in pricing right now) and spread my photos across more cards. That way, should one fail before I could transfer the photos, I wouldn't lose everything.