I havent used Syncback Pro, so sorry, cant compare.
Syncovery aka Super Flexible File Synchronizer (SFFS) is really enterprise level software.
It's extemely dependable. *Lots* of options (which can actually be a bit of a problem if you're a basic user like me).
I use it fairly basically, three sets of local backups, and one backup to amazon s3.
Even though I am a basic user, I've received great support (for my sometimes stupid questions). Have reported a couple of minor bugs over the years that got fixed same or next day. It get's updated very regularly. I've had it six years - in that time there was only one paid update (in 2012) and even that was reasonable cost.
In other words I think it's a bargain at that price
