I get absolutely flabbergasted when I see complex tutorials and large manuals (Kapersky must be one of the worst offenders with a tome the size of the New Testament) on how to operate the "security package".
The Average Joe in my experience will just bin these -- he just wants to activate the package (or even better doesn't want to know anything about it at all) , and then forget it.
That's why I think MSE / FSC from microsoft will win out.
Even the server FSC version has a nice clean and simple interface and gives the users all the information they are likely to need in sorting their system out.
Runs so you hardly notice it and does its job up their with ANY of the others. - Might not be the best but overall scores highly on all categories thrown at it (Ms Client Frontside Security -- this is the server version of MSE pacakage).
In fact you could probably make a rule of thumb stating that the more useless and ineffective the AV software is the more complex will be the documentation and the more cackhanded and complex will be the actual business of getting it to work correctly.