A number of AV products, as well as their IS cousins, are available in 3 user editions. This permits 3 installs. Must each install be in a separate OS.? May the installs be back to back in th same OS, in effect, giving 3 years on 1 OS? NOD32 does not permit this. What about Kaspersky, Norton, McAfee and Trend Micro? Any others?