Bjørn or Erik,
Have you heard of any info on the improvement of the material of A-M ring?
Sorry I forgot to reply on this one
I have never had any issues with the A-M Ring on any of my lenses, and I still have the 20-35mm 2.8 AF-D and 14mm 2.8 AF-D both working perfectly,,,
Bjørn and many others reporting on cracks and breaking,,, I have only seen this in photos online,,, not on new or used lenses.
I believe there must have been a silent upgrade in material specifications for these rings, they appear to look different, the surface texture changed at some point. But this is just a guess - I believe it can bee seen/deducted from Rolands pages last time I had a look,,,