I just removed my OEM exhaust this weekend, in favor of the MBRP Catback system. Coming from a 2010 Camaro SS with long-tubes, no cats, an x-pipe, and flowmaster mufflers (and numerous trucks with aftermarket exhausts) I am in LOVE with the sound of the truck now! I was a bit apprehensive given the few complaints of droning, but I think my baseline is a bit skewed compared to some of my fellow Colorado owners. I haven't noticed any cabin noise when cruising at 50-80mph; only on acceleration/start-up.
In light of this, I am looking to re-home my OEM Exhaust to someone who may be in need of a replacement (or the parts). The exhaust is in new condition and was removed with only 2900 mi on the truck.