Yup lol shops tend to tell you what they want so they can get your business. That's what the forums for many replace there's cats with aftermarket w/o any issue. Some will get a code that can be cleared or tuned out if you'll like. I'm on tapatalk right now so I can't see your location but do you have inspection? After my second cat (first one replaced thru dealership w/ warranty) failed I just went to headers w/ no cat. Check the exhaust manifold thread it'll tell you most everything you need to know. If going headsets SD's (Speed Daddy) off of eBay are the best bang for your buck around $220 or so. I'm sure others will chime in.