Its like cars, you can get one model that is great, the next model from the same manufacturer is absolute cr*p. e.g. BMW X3 and X5.
My own experience of Symantec products spans about 15 years, and yes, a few years back their Internet Security suite was pathetic. 2009 onwards was completely re-written and has been great. I now have it on all my personal machines, replacing ESET Smart Security (purely because it was a nicer price, the two are pretty much equal). It is sleek, efficient and offers excellent protection.
McAfee is the very definition of bloatware, eurgh.