glass is in great condition, no scratches.
This topic of the white substance has been brought up on some other forums, mainly birding forums. Their thoughts are it's some sort of oxidation or additive to the rubber. They have been like that since i can remember. I noticed there is none of it where it comes into contact with your hands or harness, only in the crevasses so it likely rubs off. I imagine it's cleanable its just never bugged me enough to try cleaning them. The rubber housing shows zero signs of degradation.