Likelihood to Recommend:Not LikelyExtremely Likely
Pros: Lots of features (backup, mirror, sync); support for cloud services (eg. Dropbox); there is even a freeware SyncBackFree version for you to try out (though quite crippled in features).
Cons: Because this is so feature-laden, some users may be intimidated by the sheer number of options available; to take advantage of some of the more useful features (eg. you need to buy the most expensive Pro version).
Overall: I use this software to backup some critical business files just in case the computer (still running Windows XP!) fails. Should that happen, I will just boot up another computer and resume my business with little downtime as I have backup of the critical files on an external USB flash drive.