STOPzilla’s scan time has remarkably decreased since the 5.0.5 version. This happened because of several updates and you don’t have to worry about the quality of scan: it had't suffered from this. The “Spider scanning” technology has been improved and some duplicated scans were removed to shorten scan time.
Additional “Lower priority” option was added to every type of scan. When scan priority is lowered, it’s run in a background. This way scan doesn’t take as many resources as it used to and allows other applications to perform better.
Also several minor fixes and user interface updates were made. A download is now smaller due to few optimizations.