I have only read a little regarding this thread from the beginning when some people had this system installed in Sevierville. My question , is it legal for a after market company to cut into the air braking system on these coaches? I believe Prevost has to certify their coachs for the US and Canada with their braking system as it was originally designed. Does this not create a Certification issue. Maybe this Company, Air Force One, is allowed to modify Prevosts air system and re certify but it appears they don't have a fail safe design.