I think the most useful feature of a "price guide" would not be to determine the relative worth of a bike; as many have have already correctly concluded that the market takes care of this. It would be more useful as a catalog to show differences between various models of components or models of bikes within a line-up for that matter. Obviously such a "catalog" would be a tremendous undertaking with probably low sales volume and correspondingly high price. I guess one could do a price guide only but with market whims and changing prices how useful could it really be except perhaps for novices/beginning collectors.
Jack Romans
Sacramento, CA