I have an 8" Ilex Acutar, which is just an earlier version of the caltar lens you have, albeit shorter. I dont know if its really a clone of a C-E or how it would stack up against one, but its a fine lens. One consideration is that its a coated lens, which your B&L is not. I have several B&L Tessars and they're good lenses as well. As for scratches and nicks, my opinion is that they often dont matter. As Dan said, let the lenses speak for themselves.

What format are you planning on shooting? 8x10? For sharpness, plan on stopping down to f22+, particularly for the corners.

Dan