No it's not an required option, but it would be very nice. I find the SED backup feature very useless, because it overrides instantly backups.

A better feature would be to have the option to create a new backup file each interal. For example, if I set an backup interval time of 30 minutes, every 30 minutes will be created a unique copy of the current scripts, maybe with date in the name:

main_2012-11-21_20-35.c (backup at 20:35h, 21st of november 2012)
main_2012-11-21_21-05.c (backup at 21:05h, 21st of november 2012)
main_2012-11-21_21-35.c (backup at 21:35h, 21st of november 2012)
main_2012-11-21_22-05.c (backup at 22:05h, 21st of november 2012)
main_2012-11-21_22-35.c (backup at 22:35h, 21st of november 2012)
...

I ask this, because in the past I've had some HDD errors. I make backups manually every 1-2 day. And after the HDD errors occured, some script files where crashed. The last backup I have was 1 day old and the SED backup was already overwritten with the broken script. So I had lost a whole business day. If I had multiple backups from every 30 minutes, I maybe lost only 1 or 2 hours. And to lost a day of work sounds not that much, but if you are near a deadline it can be really annoying to rewrite the script of a whole day.

[EDIT] While I wrote my post, Superku had almost the same idea