Careful with Combofix, it seems to be very powerful, but can kill system elements that leave you with anm instabile system. I know of two such cases, and inb oth cases people were not able to revert via system restore points and sooner or later ended with reinstalling.
At a couple of German places I also occasionally read that it is not fully reliable/compatible under x64 OS.
For routine scans I would definitely stay away from it.
Number of downloads must not mean anything. On German sites, it does not get mentioned much, and gets mediocre ratings only.
