Meritorious B?

This is an old question relevant to Kantian moral philosophy. I've done so much circular thinking about it that I no longer find my intuition to be very interesting, so I'd like to run a quick poll. People who have done work with Kantian ethics will indubitably have seen this before. I'll set it up kind of the same way Kant does: Here are three people, all of whom end up perfoming the same action. Which is, morally speaking, the best?

A: Shopkeeper A is motivated solely by making money. He reasons that if he treats his customers fairly and is nice to them, they'll become repeat customers, recommend friends, etc. So he treats them fairly and is nice to them. B: Shopkeeper B just gets a kick out of making people happy. It makes him feel good to make other people feel good, so he treats his customers fairly and is nice to them. C: Shopkeeper C hates people. Also, he likes money, and is constantly tempted to cheat his customers. And maybe to kick them, too, because he'd like it if they experienced pain. But he knows that this would be morally wrong. So he treats his customers fairly and is nice to them, because it's his duty.

I take it everyone will agree that A is less good than either B or C. But which of B and C is better?