Backing up data - with or without "sector by sector"?

Most advanced backup tools includes an option called "sector by sector". Does this option have to be checked when I backup system partition (an image)? I mean.. In case of HDD failure I have system image and I can easily restore my system on another HDD. Then, if needed, copy backuped data / files from another backup.

I do want to understand when and in which cases the "sector by sector" option is a must to check.

EDIT:
I have read the "possible duplicate question" and I understand that the option allows for backing up the disk in a way that allows accessing deleted / not wiped files. I asked my question in context of restoring system from image backup. I mean.. I want to know, if the "sector by sector" option influence in any way the possibility of restoring system (do windows files have to be in specific place / on specific sectors).

Solution 1:

The sector by sector option will make no difference to a normal backup or clone of your system. You do not have to check that option. The physical location of a file within a partition is pretty much irrelevant for everyday use.
If your disk was in the process of failing (increasing bad blocks, etc) and you wanted to take a "snapshot" of the drive to help with recovery, then a sector by sector copy will try to do that. It means you can run recovery utilities on the new HDD rather than on a failing one that could well be losing more and more data as you try to access it.

Solution 2:

A sector by sector copy is only useful for forensics ... when you want to know what the disc has been doing. You use that option to basically save the raw writes for later inspection. For you and me we only need ghost (or whatever you're using) to pack the files that are not marked for deletion and store them into its image format. This is much quicker for image creation and restoring.