I have had no problems with the Unlocker program and I have had it installed (and updated) for many, many years. I have never noticed any ads, etc. for a start I also Use AdBlocker and RequestPolicy add-ons and that also puts a crimp on any ad regardless of its origin.
VirusTotal doesn't do a live scan the sites as such, but refers to black lists, etc.
There are many different download sites that also have Unlocker and some are clear that it is Ad Supported and tells you about that (watch when installing), e.g.
http://www.softpedia.com/get/System/System-Miscellaneous/Unlocker.shtml