I am running SX 2 with the MMV as a vst, and I am not experiencing anything like what was described in the original post. I use send and insert effects with the MMV, and it has performed quite well since the 1.1 update. I have a P4 2.4 GHz, 2 GB memory, Tascam US-428, MidiSport 8x8/s. I should note that I do not use polyphony on the MMV.