Registry Mechanic - a dodgy operator?

[Higgs Boson]

I recently installed Registry Mechanic, which is obviously a registry cleaner. I used it a few times, and thankfully backed up everything it touched. Following using it, I found I couldn't boot into safe mode (problem with ntoskrnl.exe apparently), and couldn't update virus definitions, etc. I reinstalled everything it had messed around with, and my system worked fine.

Has anyone else used this product, or had similar issues?

BTW, I'm not ruling out that the problems were just caused by my own ineptness.

 

[nonchalance]

Never used it, but I have a general policy that any product that advertises itself via pop-ups on sites I don't trust is probably dodgy.