So, after scraping through the MOT last month on emissions with the after-market cat the main suspect, 1000 miles of Summer motorway miles have finally caused the dreaded cat death rattle. On inspection it was obvious that the cat was dead, the expensive bits rattling around inside. It had only been on the car for 4 years according to the service records, but perhaps that's ok for a cheap cat. I was contemplating the options for replacement, which I understood to be: 1: Ignore the rattle and drive on, and worry about the MOT next year. 2: Buy a ECP cat for under £200 3: Buy a non-MB cat from an OEM supplier like Eberspacher for twice that, or 4: Spend a grand or so on an MB unit. Peace of mind but empty wallet. However, it turns out that MB can not supply a cat for an M111 engined W124, and nor are there any in Germany. Couldn't find any other branded parts either, which left the Euro car parts pattern offering as my only (quick) option for replacement. I wonder if that's the end of OEM cats for 124's? I imagine there wouldn't be many takers anyway at the prices MB charged, but it still surprised me. The ECP supplied unit was delivered promptly, and my mechanic had no problem fitting it - I had been worried about this after a bad experience with a cheap centre section recently (which has since been scrapped and swapped for OEM. It just refused to fit properly). All that remains is to test the longevity, but with such a low price I won't expect too many years' service. It's got a 2 year guarantee, so at least I can rely on that much. I have renewed the Lambda probe / O2 sensor too, and I believe there are no current issues with the motor that will cause the new cat to die young... but we'll see.