Mike,

This is attributed to MS: Microsoft conceded last year that its security software was intended to offer only "baseline" performance, saying it wanted to "give customers a good reason to pay for their [security] products" because that would create greater diversity in the market and make life harder for malware writers.

We switched back to Norton a few years back after it woke up and lost the bloat, delivering efficient systems that no longer paralyze your machine. Very happy with the decision. These days there are fake sites promoting various products but in mainstream reviews the various mainstream products jostle for the top position so you might as well pick one and stick with it.