Can't say that.
The human brain (if you have one) is the best tool to prevent the installation of spyware, malware, and other potentially unwanted software.
Not any human brain.
Only a trained human brain that has interest in maintaining a PC is the best tool.
I know some of my relatives just want to watch Korean dramas on the PC and they downloaded Qvod and Funshion then 'Next' through the installation and ended up with all sorts of adware/bloatware.
Most people just treat the PC as a tool, I find a PC is kind of like a pet (I run CCleaner to clean the junk, schedule trim and defrag, run a quick scan when MSE complains etc).
I was actually refering to an old IE version slowing down due to a large Restricted Sites list.
Internet Explorer in Windows 8 has Enhanced Protected Mode (along with ActiveX Filtering and numerous other security features), so surely these would render SpywareBlaster unnecessary?
But Enhanced Protected Mode is a good point.
Actually I never thought about the relevance of SpywareBlaster and sometimes I actually forgot about it as it never slow down my PC or nag me.
Seeing all your posts made me think about it