FS on the hard drive just seems volatile to me. Simply, harddrives are corruptible. When it starts to go bad the whole thing just becomes a black hole. Well, I know I have been through that, power cut offs, harddrive is messed up.
It won't help you having the FS in the rom if the hard drive goes kaput, you'll still have lost your data. The handy thing about having it stored on the RDB or in L is that it's easy to upgrade if a new version is released.

I've been using SFS for quite a number of years and haven't lost a single bit of data with it or had it crash or lock up on me...
