The other issue is for REalband you have to Load minihost or PLug flop in for every instance you want to use your vst. I use Sonar too and you don't have to do this in that program. But in Realband I was able to get most of my plugIns to work. The only ones that wouldn't was a series of REaktor instruments I bought from Musicrow and it doesn't align their reaktor instruments properly. But every other plugIns work, the Arturia's KOntakt instruments and the various Cakewalk synths. So I am happy.

Before knowing about these I was unable to get any of my VST's to work, and when they would it was I could only use one at a time. and I didn't have the words to explain the issue now it's fixed so while it is cumbersome you can atleast explore Realband.