It's a "clean" thing .... the VLT2 sounds better, has more options, more voices etc than the built in unit .... although, the one inside is DAMN good. I just don't need to carry and set up more stuff. 90% of my work is fine with the minimal setup. The real "meat" comes from the other side of the mic, and I'm in control of that without any gimmicks. I just want to give my audiences the biggest, fullest sound ... and do it better than most of my competitors in the area ... for a slightly higher price. That way, we're ALL happy.