I have a VP150 and have had similar questions in the past. I was hoping to hear things like "just get a second VP150 or add a VP100", but instead, I hear that the VP180 is significantly superior to even dual VP150 setups. That is frustrating since I don't like the idea of having to auction off my VP150 to get a VP180. I just fear that I won't get enough out of it to be an "easy" financial upgrade. It is definitely on my list of things to look closer at though. I hear that going from a VP150 to a VP180 is a bigger upgrade than going from M60 fronts to M80 fronts.
I will probably get another set of QS8's first though, but like I said, it will always be on my list...
