Yet another reason to not pay money for CDs. However, kudos to F-Secure for being able to make a stand.
My experience with F-Secure is limited to one computer, mah poor uncle's wee thing, an aged PC with a Pentium CPU of some considerable vintage. Under the F-Secure regime (or at least, under one of the antivirus program updates, potentially since fixed) IE would take literally minutes from "click" to action. It was actually fairly difficult to uninstall F-Secure too. But once it was gone and Avira was installed, his machine breezed through normal operations like normal.