short cage = yes, less chain to wrap since you dont have to wrap around a big gear.
Most brake systems are NOT interchangeable. SOme work with DOT3 only some mineral spirits only, some can use both. All have some adjustability, but most all move a different amount of fluid in the lever stroke. Its been years since Ive been in the game, but I remember that much. Get it good with a reputable shop with employees who really ride bikes. They will have first hand knowledge about whats good and not etc...good luck. keep the rubber side down