I haven't heard the MO recording of it, but for my money, the Bernstein recording of it with the NYP and Vacchiano is, for my money, one of the best 2 minutes of brass playing ever recorded. I'm not 100 percent sure, but I think the version they're playing is excerpted right from the Third Symphony (more brass, different key than the excerpted arrangement). Go buy this CD!!!
http://www.amazon.com/Copland-Appala...e=UTF8&s=music