I know way better alternatives to it, however it does its job well.
I once used it as it was interesting for me how this software handles the task of cleaning my PC. The result was quite satisfying I have no quibbles to it in terms of the result, but I didnt like the settings, number of functtions, as some competitors offer better things for deeper cleaner of the register without touching important files.
But there are no viruses and thats cool, some guys told me beware of the Avast.