Is this true about the Fostex MR-16HD?

The Good: this baby is easy to use and records clean. The Bad: we filled the 40G hard drive after 24 sessions of priceless Fezz music. The Ugly: surprise! once full--you can't free up the memory--it keeps all deleted tracks as "hidden" files.

I saw this as a review on musicians friend. Even though all the other reviews are good, this review kind of scared me. Does this mean their is no way to erase things from the hard drive? Can't you reformat the drive? I don't think they made it where it is a brick once you fill the hard drive, but I wanted to double check because of this review.
93' Mexican Stratocaster

LTD Viper-50 --- Active EMG's

Currently using a cheap crate amp