You can get same sort of thing free with CCleaner,Glary's Ultilities and System Ninja,I've used them and they do help keep your PC clean ie having too many invalid files and leftover broken registry files etc...
Some say its snake oil so YMV ,personally I think a lot of users do use CCleaner,Glary's ultilities etc like myself.
I do use registry cleaner in CCleaner and Glary's ultilities with no issues(their default scan mode),System Ninja I just use junk cleaner.
I'll say never had any problems with those over the years(I did use CCleaner and Glary's lastnight ),yes I've all important stuff backed up like you should regardless of whether you use one of the above software programs or not.
Btw first time I used System Ninja I got 4GB of free space back ,so if that is snake oil I've more please.
What do you think of TuneUp Utilities 2014?
Offers nothing over the free ones is my humble opinion.