A trumpet player tends to sound best on the mouthpiece he can SUPPORT. Granted a second line G doesn't need a heck of a lot of support. Very "little energy demand" to use Maynard's words.
That said I've noticed (and this probably doesn't relate all that much to the topic or condition):
Trumpet players who use large mouthpieces but don't play or practice long hours usually sound MUCH better after they switch to shallower/smaller mouthpieces. This ought to EXCLUDE Mark K.
Unless a trumpet section is fairly powerful they will always sound better and create a more sonorous sectional tone when using something more around a Bach 7 to 10C (Gawd i HATE mentioning Bach mouthpieces in any kind of positive sense. i offer these thoughts only as a measure of mouthpiece size.
Sometimes I feel like going out and buying the trumpet playing associates in the local community college band a collection of Schilke "A" and "B" cup mouthpieces. But I think I'll save my money and get my whole Al Cass collection cloned. Better mouthpieces.