Everyone seems to want one horn that does everything well: jazz, classical, shows, you name it. Well, it's not quite so easy. A horn that gets a great dark symphonic sound can be downright tiring to play in a big band for four sets. A snappy jazz horn will get you shown to the door in many symphonies.  That being said, these horns do their best to hit the mark in the middle. I like the idea of using a medium bore tenor trombone for several reasons: they work well in a pit orchestra for a stage show, they often record better than a large bore tenor trombone, there's nothing wrong with a bigger sound when playing in a jazz combo, and many first parts in a symphony or band are better played on one of these than they are on a big moose horn symphony model. Think French, think light, and bright. For example, Ralph Sauer, former principle trombonist of the Los Angeles Philharmonic occasionally plays a Conn 8HT with a .525" medium bore slide and a Schilke 50 mouthpiece for lighter works.  He also frequently uses a dual bore .525/.547" slide on that horn too. He says he can get a clear efficient sound that goes to the back of the hall without having to over blow the orchestra.