These are all to be avoided! Even the airport ATMs have a worse rate than elsewhere (I suppose airport rent must be paid). The roadside money changers everywhere in Bali offer at least 10% better rate than at the airport, and I found them to be honest and reliable even when it looks very ramshackle. There is little reason or benefit to use banks and more formal places to change money, and I had no problem changing a wide variety of bills in varying condition; they know how to test for counterfeit!