While I wouldn't necessarily tell anyone to not use AV software or Reg Cleaners, I would say monitor things closely. Seriously, make a backup before using utilities like this.
We had to contact this company directly because they were removing Registry Keys SONAR needs to run. I've been told they resolved the issue (they were quite helpful), however this impacted countless users.
All I'm saying, is make a backup before running anything that touches your registry.
Best regards,