Good point, however the reason why I'm running full scans is that a) I strongly suspect there's a virus due to particular PC behaviour or b) I know there's a virus because I can see it's behaviour. Also, when I leave the site (or return the computer) I must be 100% certain that all malicious software has been expunged from the PC. As an IT Technician I'm routinely scanning PCs I know have an infection. I'm not using Full Scan on an uninfected PC as a routine system maintenance item. Further, as I'm charging for the service, there can be no mistakes. Hence a minimum of 2 full scans with MBAM and on the tricky ones I have to rope in an additional 2 scans with Trend's HouseCall (which truly redefines the word slow, but in my experience has been the most aggressive scanner of the lot), not to mention fast scans with more specific Rootkit detectors etc. (Off topic: And just to keep life interesting, every now and again I see a virus that no scanner can find. Last time a client saw this they had GFI A/V, and GFI remoted in, found the virus (which was in an obvious location in the end) and added it to their protection tools. I think I submitted it to MBAM at the time.)