Not using a magical musical instrument I believe really waters down the bard. Oratory is no match for an extra 4 or 5 spells a day, massive bonuses to your Fascinate/Suggestion combos, and other mechanical goodies. Hell, war drums don't even cost 300 GP and they give +1 to attack and damage when inspiring courage.
Its like limiting yourself when you really don't have to.
Its like limiting yourself when you really don't have to.