I use ThreatFire now with avast!,it is said to be behavior-based and a good partner to the traditional AVs.But when the new version of avast!5 come out,it will be possibly with HIPS.Since 2 HIPS running together is no great idea,I'll either uninstall ThreatFire or turn off the HIPS part of avast!5(if there is a opt out tick box or something).
So I really hope the HIPS part of avast!5 work
tested better than ThreatFire and my security solution be all in one
,otherwise the choice will be difficult to make.