FWIW, I had a 340Mb Microdrive fail on me and I decided that it's not suitable for a mobile application like photography. These days I shoot from several 256Mb flash cards and upload to HD or CD-ROM after the shoot.

Speaking of which, have been looking at devices like the Gmini and FlashTrax, but have not decided to take the leap yet. the Gmini is seductively small, but doesn't display RAW format files and it doesn't appear that photos are a large focus for the product.

The FlashTrax, on the other hand, is designed for photos, but it's bulky. However, it uses the same HD that my laptop does, so I have good confidence in its reliability.