By my self I use McAfee VirusScan 8.8 Enteprise and SpyBot S&D 2.0 to protect my computers at home. Without any large performence impact and any big problem. You need to tune som of the default setings to get a good performence, like to just scan write to disk and not read for every thing. You can also list processes in sensitivity to get different kind of onaccess scan for different applications dependig on hove likly thay are to be a carrier for virus.
But I agree that the home edition in McAfee product line can be a litle to match becaus of ther boundling of different kind of products that you probebly wan't to have other solotion to. So because of that would stay away from them an just go for the VirusScan Enterprise line if it is possible for at privat customer.
The closest I could find to "VirusScan Enteprise" line in the privat selction is "McAfee AntiVirus Plus". And then add SpyBot for surfing security SpyBot is free to use for privat purpose but is to by for comersial use.
Her can you find SpyBot on ther home site:
http://www.safer-networking.org/