The genuine hangers for my (old) cars from the stealer have never lasted more than two years. Maybe I'm the only one buying them, and they all date from the year the car was made. I'm talking about 115, 123, and 107 cars, with 1981 being the most recent. YMMV.
Simply get the correct part for your specific car! The proper hangers should easily last 10+ years unless you do a lot of "off-roading." Some (but hardly all) aftermarket rubber hangers are of very poor quality and I've seen some fail within months. That has not happened to ME with genuine Mercedes hangers (that are correct for the application and model car). Marshall
-- OK Don, KD5NRO Norman, OK "Even if you're on the right track, you'll get run over if you just sit there." Will Rogers '90 300D, '87 300SDL, '81 240D, '78 450SLC, '97 Ply Grand Voyager