Old vs. new, easy. The old bikes are old because they lasted long enough under the rigors of use to actually become old. New bikes, of today, will not ever be really old because they are manufactured from materials that have a practical life limit. And while it can be argued that steel bicycles have a life limit, they do not deteriorate from common environmental exposure to heat and UV radiation or incidental knocks and bumps. Not to mention unpredictable failure modes, unfriendly to the environment manufacturing processes and lack of recyclability and susceptibility to damage that is difficult to identify and assess.