Specific e89 dowpnpipes, flex or no flex

Neg89

Specialist
Jul 4, 2021
67
6
0
Let's me explain my situation only after one and a half year and 15,000 km my new KW autowerke down pipes are completely disintegrated at the flex part ,that crack was so big on the flex joints that it's almost fell into pieces. please tell me is the flex part necessary ? Before I put on the downpipes the first time I specifically search it for the flex part, because I was uncomfortable for putting on just the solid pipe without any Flex joints, by the way my engine mounts are new and they are stock.
You can look at the video how bad it was