I got very tempted to jump on the 40-150mm R all black lens which looks so gorgeous, and then realized the mount might be plastic. It seems that many companies are deliberately leaving out any information on the mount and even showing front and side images only. Now, there are many compromises i'm willing to accept for lens size and weight but a plastic mount isn't one of them. Would the 45-200 be a reasonable alternative? It looks heaps bigger and heavier and gets moderately positive reviews.. Am I plain out of luck here or do you guys know of any upcoming zooms that could be interesting?