There's nothing that Trail Boss does that Red Dot, Titewad, Bullseye, Ramshot Comp Clays, Hodgdon Clays, Extra Lite, Clay Dot, e3 and a host of other super fast powders can't do other than bulk up your case to ensure no multiple charges. That might be worth the extra cost for some but not for others. Oh yeah, it smells funny too. When you get down to powders like Unique, light loads get really smokey and spit out a bunch of flakes but if you don't mind that, then it works too and it's a bit more bulky.
If you like smoke, try Alliant BlackMZ and fill the 38 case as you would TB. Lots of smoke and performance like BP without the fouling or corrosiveness. Same as American Pioneer Powder.