@YoKenny: look like a misapprehension... I'm sorry
Where did I say that SpywareBlaster has any influence on the HOSTS file?
You did not said, It was just a suggestion by me, Immunize hosts instead of other places

If software can set the HOSTS file to Read only then malware can undo this and have its way with the HOSTS file.
same about anything else... if you immunize IE, malware can remove those URL from it

Restricted Zone Immunization has absolutly nothing to do with the HOSTS file.
I know, but when URL be blocked (redirected to localhost), no need to immunize again in IE or FF, because it would not load... IMHO
In IE8 I notice little difference in startup speed with or without SpywareBlaster's protection (Immunization).
it would not slow down ONLY IE, it would cause slow down in loading all windows application, so you would feel your windows is not working in that way that you like and you wish, you would see your RAM and CPU is free, but system is slightly slow...
Windows Defender detects HOSTS file modification immediatly and notifies you if the change should be approved or not.
Thank you, I would check it in the Windows Defender options/features. look like useful

By the way, I am rid of Avira AntiVir as it does not meet my needs.
but it's same what I like and want and need, really really nice detection rate, fast scan speed, very very light on resource and secure, the latest update has added minor behavior detection (something like HIPS, but not like a full guard) for the thing related to browser for even more security, just I wish if Avira could fix that problem about the delay it cause for network operation on slow internet...