Both of my Catalyst Converters is broken inside. This is expected as the car is 10 years old. I took it to my local indi and I got a quote of £1700 for genuine MB parts and £1400 for after market parts. I found loads online total £400 for both. I do know that the quality will not be as good as the genuine parts and they have titanium in them, but my indi says that the cheap parts will not last as long. I can buy 3 sets of these for the money of the one pair. My question is , do I get the cheapies or the expensive ones ? Will it make a difference in the sort term ? Any advise would be appreciated, please !