The biggest difference I've noticed is the sharp-Ness of the note between maple and rosewood. R/wood seems abit flat and dull where as maples a sharp struck note.
To be honest the case isn't really needed with the Tele hung on the wall but I really don't want to ever sell this guitar and the idea of kids/grankids pulling this out the loft in 50/60 years time is too cool, hence wanting the retro case to go with it. I'd be in the market for a martching amp in a few years too but I'll see how I go.