Given the condition of the gasket, I was assuming it was leaking to some degree. I saw black residue on the back of that pipe, but it was also pretty dark when I finished and didn't take a pic of it (could also just have been road grime.) Never got a code so maybe no issue. Maybe hoping I found an "issue" that was solved with the swap.
BTW, thanks again for your help on the install.
08 E90 | Jet Black / Black | 6MT
Mods: RAC RG63 w/ Pirelli Corsa 255F/285R | Akrapovic Evo Exhaust | OEM Blacklines
Winter Setup: OEM 18s w/ Nokian Hakkapeliita R 245/40-18