I also saw the comment last week speculating that for the same money you could get a 21/4 CV and a 35 Biogon and get better performance. You would still end up with two lenses to fumble with, drop, collect dust, require UV/IR filters, or bang together in a camera bag. A 21/4 CV lens is not in the same league as the 21-35 optically, and a 35 Biogon is nowhere near as well built. The 21-35 was a halo lens for a company with cash to burn, it was designed and built like one, and if you take the time to put a calibrated M8 system together, it may be the only lens you ever need.
Dante