Another benefit of GM status over FO is the priority security lane at many airports. I find it a huge time saver at the Delta terminal at LGA and a modest improvement at JFK T2 (despite my gates invariably being at the point in T3 farthest from). It won't change things much at the Marine Terminal where the LGA-ORD shuttle flies, but that terminal is easy and as GM you have an excellent chance of an upgrade on most shuttle flights.