"Sweeney" is driven by the woodwinds and reeds, and the brass is just there for color and some hits. It was a "low impact" book, which is somewhat rare in musical theater these days for trumpeters. But I didn't mind the change of pace one bit. One horn (my B flat trumpet) and 2 mutes (straight mute and harmon mute): that's it.
"Legally Blonde", however, is a fairly busy show for the trumpet, doubles flugelhorn, and uses three mute (straight, cup, and harmon- with stem in and out). The first hurdle of this score is the rhythm. Lots of rock 'n roll/pop rhythms. Nothing insurmountable, but it's still something that keeps you on your toes. Second, the range. Yikes. For shows like this (that keep the trumpet in the stratosphere), I hit range exercises pretty hard to "train" my lip. I use (and recommend) the book "Advanced Lip Flexibilities" by Dr. Charles Colin. Great variety of exercises that kick your butt (in a good way).
Despite all of these obstacles, I secretly love the challenge that "Legally Blonde" poses! It drives me to practice more, to practice different techniques, to build up my endurance and range, and, ultimately (and hopefully), to become a better musician.