I "upgraded" from a Pioneer 141fd (60") to a 65vt50 and still own a Pioneer 500m. The 65VT50 is ever bit as good as the 141fd which is essentially equivalent to the 600m. So you will not be unhappy buying a VT50 but keep in mind the picture quality isn't really better than the 600m, but you do gain 3D. if you can wait for next years models, I would wait..
M&K LCR-750s Fronts and Center
M&K M-4T Surrounds