I would like to add a couple of lenses to my collection. All that I have are the early Crossed "X" type except for a 35-80 xi that I picked up from somewhere. What I would like help with is not the function as much as the quality over the years. I have noticed that the window/range scale dissapeared on the newer lenses. I am concerned about the weight of the newer ones being so light, they feel cheap. Is there a web site or someone with knowledge about construction/quality/evolution of the Maxxum line of lenses?