Just do some test between CCleaner and System Ninja Standard Settings from each program : - System Ninja temp file scan = 497MB files to be removed - CCleaner temp file scan = 364MB files to be removed System Ninja removed additional files, mainly thumbnail.db files located in every folder, more temp files in the appdata folder. From what I can tell, seems very safe. Analyze your system, and without removing any files, see what it finds. Windsman. PS : Disk Cleaners should be judged by their Safety; not by the data Size they remove.