[VGM6]

I've been looking at downpipes for a while now and I currently have the Akrapovic system installed and I love the louder grunt but wouldn't mind some extra sound and better performance going cat-less. Now I've noticed many brands happen to have a flex pipe on the down pipe similar to our stock DP's with cats. However only one brand which is ER's downpipes does not happen to have it.

Considering that the price of the ER downpipes are significantly lower compared to the others, what would be the need of the flex pipe. My only assumption was that the flex pipe would allow for better fitment or if the engine and exhaust move under full load that it would not cause any damage to the turbos and or exhaust after long term use do to it not being able to move.

For those of you who dont know what I'm talking about its the part in the downpipes that has mesh or in eisenmanns case the ribbed cylinder.

If anyone has experience and wouldn't mind explaining I would appreciate it. Thanks in advance.