As far as Colnago's go, my experience is that the early 70's Colnagos were great bikes and by the early 80's they were no where near the quality of ride as the earlier.
I owned an electric blue '72 (dead and gone now) and now own an electric blue early '80's. I purchased the '80's because of my fond memories of the former and there is really no comparison of the two. The 70's was sure footed and comfortable - the 80's angles too steep and twitchy - a very nice bike bike nothing like the earlier. In comparison, my recently crunched '73 Pogliaghi had a wonderful ride not unlike the Colnago. Brian Baylis will be resurecting that bike (also electric blue).
Roman Stankus
Atlanta, Ga.