I took my Jeep there to get a complete exhaust system from the header back. I was given a fair price and dropped the car off Monday morning. When I picked it up it had a high pitched whistle coming from the front of the vehicle. I took the manager for a ride so he could listen to it. He confirmed the noise and told me to bring it back when I had time. While I had the vehicle I crawled under it to see if I could find anything that might be causing the noise. At that time I noticed that they actually re-used a section of the previous exhaust, which is not what I paid them to do. I took the Jeep back the following Monday and they said that they couldn't find anything wrong and that it must be one of the parts that I had purchased on my own, a flex pipe, and for another $109 they could fix it. I declined because I knew that wasn't the problem. While diagnosing the car myself I discovered they cross threaded the new O2 sensor I had them install. Now the car can't be driven until it's fixed.