I have used F-Secure with a great deal of success. My only complaint is that if the PC doesn't have an "instant on" wireless connection, it doesn't catch many threats. Once it connects and updates its database, it does an amazing job - especially with the recent job I did on Protection Center rogueware. I agree that it would be nicer to have a bootable USB device where an update could be done just before beginning a job. I have clients that access the Internet using a USB modem.
Thanks for the article. I will be checking out some of the others you listed especially those that can be USB based (even my not-so-much-liked AVG)
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