Joe the reason I asked is we have "chipped, modified" probably 250-300PSDs, and just did 2 02 PSDs for a comparison, one with the Western chip, box and exhaust, the other with the ATS chip and exhaust. Both had K&N filters. Both equipped with pyrometer, boost gauge and trans temp gauge (the stock Ford trans temp gauge is a JOKE). The pyro thermo couple was installed in the bottom of the exhaust manifold on the drivers side rear. The EGTs on both were very close in the performance mode when heavy footing it(1500-1600degrees). Be very careful as you will create problems in the performance mode if someone keeps the hammer down. Educate your customers on the do's and dont's of pulling heavy loads and tell them to watch the pyro very closely when in the hot rod mode. The RV\TOW mode doesn't create enough EGTs to really worry about. Both trucks performed about the same with the ATS chip being slightly faster in the HOT ROD mode while the Western chip was a little healthier in the RV\TOW mode. I believe these 2 manufacturers are the best available and they are too close to call which is better in my 02. Bottom line is the trucks are really amazing when "chipped" and when you really want that "little" extra, install the propane!!! WOW!!!