netchk

We use shavlik's netchk protect to patch our servers. We have about 30 physical servers and about 30 virtual servers. We need more licenses. Sccm was suggested instead of netchk because it can manage the virtual servers better???. We use wsus for our workstations. I prefer netchk because I can control the updates by pushing instead of the clients pulling (wsus). I was told that with sccm, the patching can be push and pulled. Is this correct? Thanks.