I have three steel bikes on the road, and one aluminum. I am not interested in plastic, but I have nothing to dislike about them either. I started collecting with what I still have. All the frames have been built up and starting just as frames— all qualifying as vintage. The aluminum Vitus 979 is well-known to not have the "nervous" vibration transmitted throughout the frame that is said to be usual by owners of modern Al frames. Modern aluminum frames differ from earlier aluminum frames in a number of ways. Early aluminum frames such as the Vitus, Allen, Bridgestone used tubing gauges that were of similar diameter to Reynolds, Columbia, Tange, True Temper and so on steel alloy tubing. They were typically bonded together. A small number of the Vitus 979's's were pegged at the BB for stiffening. All in all, these early aluminium frames felt very similar to steel frames, except in my experience at least, the unpegged Vitus tends to flex. I'm merely a sports rider who does not enter vintage competition, so any flexing is of no concern unless it causes autoshifting. (And so what? ... get over it!) All my steel bikes are a great ride too, some being stiffer than others — after all, they were constructed as racers. The Vitus is a joy because it has the airy feeling of just being lighter, but smooth and silky on tubular tires.
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Vitus 979, Simplon 4 Star, Gazelle Champion Mondial, Woodrup Giro, Dawes Atlantis