All very good points to consider giddyup. We are still in our POC now for almost 3-4 months and nobody can decide what they want to do. We have brought in other vendors to look at for their NAC solution but none of them have been as well integrated as Trend into a VMware solution since we are 100% virtualized for 1,600 desktops. Today like I said everything runs smooth and easy with OfficeScan across our entire environment. We take the hit for A/V updates at 3AM each day and you can tell based upon the spikes we have on our storage during that time. But its ok since its so early in the morning and nobody really notices the slowness for that 30 minutes or so. We tried using SmartScan with OfficeScan but ran into all sorts of slowness problems and filed a bug report with Trend, so until its fixed we are still using the Conventional Scan engine.
But as the more I read and think about your comments about Deep Security you still bring up a very good point. With everything being so integrated together to work it may be a huge pain to upgrade everything correctly and to keep track of all the versions so that everything is supported. We are having a similar problem right now with upgrading to View 5.2 in which we found two bugs so we are stuck on View 4.6 until the next version of View comes out. This also keeps us from going to vCenter 5.x and is also holding us up from using vCenter Navigator and some other things. When everything works correctly VMware works great but with all of the different versions its hard to keep track of upgrade paths and then you tie it into a 3rd party solution like Trend and it makes it even more complicated. Feel free to email me directly if you want to talk more.