Not a profound post, but I am a brand new owner of a MacBook Pro, and, coming from a PC-only user background, I succumbed to thinking I needed to install an antivirus--Kaspersky for Mac, in this case. That was about 2 weeks ago, and, after incredibly sluggish performance and many semi-freezes of the computer, today I uninstalled KAV--and it's amazing how "snappy" the Mac is again! I haven't seen any mentions of Kaspersky AV for Mac on this forum, so I just wanted to add my experience. It definitely gives me the "willies," not having an AV installed, but I decided to trust the advice of the more experienced Mac users on this forum! Thanks!