I did a small very unscientific test. I installed Superantispyware Pro, Winpatrol, Hitman pro and Prevx free. Then I started installing 5 nasty malwares. SAS was almost blind preventing only one from installing. Winpatrol and Prevx both warned of the infections. http://img80.imageshack.us/i/sas3.jpg/ http://img231.imageshack.us/i/sas6.jpg/ (look at Winpatrol warning!) The system was soon full of pop-ups. http://img44.imageshack.us/i/sas5.jpg/ I scanned with SAS, cleaned and rebooted. It could remove quite a lot, but after reboot only Prevx could run, and malware prevented all execution of other programs. http://img26.imageshack.us/i/sas7.jpg/ I scanned with Prevx, put licence key, cleaned http://img39.imageshack.us/i/sas8.jpg/ and rebooted. Now the PC was clean, but file associations for exe-files had not been corrected,so the system was still unusable. http://img401.imageshack.us/i/sas9.jpg/ I booted to safe mode (command prompt), restored a clean system and booted. Evething was ok now! Programs could start, and Hitman pro also told system is clean. Prevx rocks! Ps. I've found Winpatrol very useful in my tests! SAS real-time protection seems poor,and SAS cleaning capabilities seem clearly inferior to Prevx.