After careful consideration to the concerns and allogations by this consumer, it is our conclustion that automotive exhaust systems deteriorate from the inside out due to corrosion from the combination of air and moisture. Though any welded seams will collect surface rust after a period of time, the integrity of the repair will not be compromised. Being unable to determine specifically which customer had this particular concern, we have been unsuccessful in pursuing their satisfaction. However we would like to express our devotion to our clients and assure all of our customers that all repairs made to their vehicles is done so with the utmost of quality and highest integrity. Sincerely, Owner - Holiday Muffler and Brakes.