I was just messing around on this. It's quite a difficult, high piece. I would say that the Base Trumpet part (not actually a bass trumpet, just a quiet, base-line sort of trumpet) is quite hard as I have a friend who has done Grade 5 cornet and says that even he can't go that high. Trumpet 1 is the best choice for more intermediate players, and Trumpet 2 is impossible (look at some of the note lengths!).