I have had this for about 2 weeks now and feel i have to write in to counter the flawless reviews this product has had so far on this page (which was one of the reasons i chose it over other brands). This review is based on using it on Mac OSX (on a macbook pro) and Windows XP (on a desktop PC and also on 'bootcamp' on the macbook pro). It was connected via FW800 to the MBP and via USB2 to the desktop PC (not simultaneously - i could not get it to do this despite Western Digital's claims that the drive can connect to macs and PCs simultaneously).
The Positives:
-With FW800 it is incredibly fast, I am very impressed at the speed.
-It is very nice looking and smaller than i expected from the pictures.
-The button on the front is well thought out and is a very useful idea.
The Negatives:
-Sometimes the drive doesn't mount. In both OSX and Windows there have been occasions where i have switched on the computer and the drive is not there, i have to take out the firewire cable switch off the drive and reboot for it to show up.
-Noise. Contrary to other reviews i have read the drive is very noisy. The fan can be easily heard above my macbook and PC, and when it is reading or writing it makes quite loud 'drive' noise. This is especially bad when it is placed on a hard surface.
-Goes to sleep too easily. If you haven't opened a file on the drive for about 5 minutes, the drive sleeps and the noise goes away (which is a plus) but when you then try to access a file you have to wait about 10 seconds for it to power itself back up from sleep mode, which gets annoying when working on things.
Verdict:
All in all, i didnt expect to be writing this many negative points, perhaps my one is noisier than others and perhaps there is a way to stop it sleeping all the time, but then i will have to choose between constant fan noise or long loading times. I am disapointed, low noise is a crucial factor to me as i work with audio.