I'm probably late to the party, as certainly you FL frequent flyers already knew this. As the measurements were taken on all of my leather jackets, it was discovered that they really had little to do with quality of fit. Example, my G&B A-2, which fits nearly perfectly on my shoulders, and has a nice "square shoulder" look, is a bit wider than some other jackets that actually "droop" at the shoulder. I do not care for the droopy shoulder look. My USWings G-1, the narrowest of all my jackets, has a spot on fit at the shoulder. So it must be the way the overall cut is made, and the construction of the coat as to how it will fit. I have a G&B Navy G-1 ordered, in a size 38. Spoke with Jenna today, getting all of the measurements for both the 40, and the 38. The Cockpit G-1 that recently arrived might (might) just stay in my collection. By the way...how many G-1's is too many?