If I get an X-Pipe with secondary cat delete it will not throw a CEL because the primaries are still in place. I'm really trying to figure out if I'll get tired of it as a few members have stated that it's gets annoying for a DD.
If I go ESS or Evolve they can always reprogram my tune for a catless setup.
E90 M3 Jerez Black/Bamboo Beige 6MT - BMW CCA
Dinan Rear Exhaust, Secondary Cat Delete, Dinan High Flow Carbon Fiber Intake, IND Painted Reflectors, BMW Edition Grills