There've been a lot of good threads recently covering exhaust. It seems like the downpipe is the biggest power robber of the CM exhaust system. I'm thinking about changing it out to a catless one, along with the Borla axle-back exhaust. It's not as good as a full catless exhaust setup, but it's a lot cheaper and likely to produce similar numbers.
Did anyone have to have the Akrapovic CEL delete installed, or can I hope to pocket that $300 and rely on an O2 sensor install? I'm a little hesitant to overnight my ECU to get it tuned (currently relying on a JB+), but I'd rather spend ~$500 on a tune that deletes the CEL, than $300 for a simple CEL override.