I have the VP100 and M60s and I am very happy with the results. They are a good match. I would recommend the M60 over the M50 just because you already have a VP100 and the M50 has a slight tonal difference due to the 6.5 being used for the midrange instead of the 5.25 driver. I was space constrained in my cabinet so I went with the VP100 and I love it. For TV viewing, the m60s have sufficient bass in my room and I leave the sub turned off so I don't wake the kids. With the m60s set to large, and the VP100 crossed over at 100 hz, the bass from the center is routed to the mains and they perform very nicely.
I bought a new house and am planning on keeping the m60 vp100 combo in the theater, and building out the family room with a new set of in cabinet m60s and a vp160. You will really enjoy your setup. The differences these guys talk about are pretty subtle with the only major difference being the vastly better bass response of the VP160 vs the VP100. Properly setup bass management will make that extension difference fade. Tonally they are quite similar. It's much more important how you setup your system than the small differences in the speakers.
