We do most street reconstructions on 22 x 34 for the 11 x 17 half scale reason, we have a scale bar on it that represents the 22x 34 scale and even the Contractors seem smart enough to figure out that if they slap their scale on the scale bar and it does not come out right they should try 40 scale instead of 20 scale. We have not really had a problem yet...except when someone sends out things scaled to fit, then everyone is pissed!