Ever hear the term, "A necessary evil?" That is what AV is.
No one product is going to be faster at catching threats than the other. Each vendor leap frogs each other every definition they make.
What sets each apart is the management, the ease of use, resources used, and support options. If you are buying based on cost, god help you.
All these people here complaining about SEP missing something.. 50% of them have on AV enabled. The other portions, have local admin privileges applied, or no tamper protection... Go to a competitor website's forums, and I'll bet my paycheck that those users of those respective products have the same issues we do.
The difference here, is we're all trying to be supportive of each other and better the community in insisting that users submit the files to Symantec, document their findings, and we suggest ways to improve security.