I've run several devices from usb flash for years and have always followed the advice of Martin Michlmayr to use -noatime. Through the years I've had a few crashes, but they have consistently been on cheap usb devices. My advice is to use noatime and sandisk memory, other measures give little in return.
(Skickat från min mobiltelefon, därför kanske något kortfattat.)
I'm running lenny on my nslu2 on a usb flash stick and found a few guides on how to reduce wear and tear on it but not sure which ones are upto date/relevant. Could someone have a look at these and let me know what ones I should be doing is seems ott to do them all.