Here is a fruit platter that I quite literally threw together in about 20 minutes for a church event a couple weeks ago. I paid something like $20 for a bunch of fruit that would have probably cost at least twice that if I would have bought it pre-prepped. Moral of the story: buy whole fruit, prep it yourself and pocket the extra jingle. As an added bonus, you get to practice your knife skills.
Of course, when you include fruit that is prone to oxidation (turning brown) like bananas, apples, etc., you need to toss them in a little citric acid before plating to prevent the dreaded brown nasties.