It will allow you to clone your current system including the mbr without actually copying unused space that dd does hence doing it faster
Since its reading / writing on a filesystem level you can only use it on a supported filesystem, on the contrary to dd, which works on a device level, allowing the copy of any filesystem.
Clonezilla's front page has a list of the software's limitations:
- The destination partition must be equal or larger than the source one.
- Differential/incremental backup is not implemented yet.
- Online imaging/cloning is not implemented yet. The partition to be imaged or cloned has to be unmounted.
- Software RAID/fake RAID/firmware RAID is not supported by default. It can be done manually only.
- Due to the image format limitation, the image cannot be explored or mounted. You can not recovery single file from the image. However, you
still have workaround to make it, read this.
- Recovery Clonezilla live with multiple CDs or DVDs is not implemented yet. Now all the files have to be in one CD or DVD if you
choose to create the recovery iso file.