I've taken the plunge and installed the latest Zonealarm Pro 2010 to Co-exist with Avast pro 5. Surprisingly theres no wait at boot-up as per previous versions of ZA, which to me is a HUGE! plus! Apart from the interim pop-ups and having to allow access to a few programs ZA pro 2010 seems to be living more cozily along side Avast! than what Outpost Pro 7 did. Theres several good reviews floating about, about this version so for now, unless anything untowards happens I'll keep it installed.