In Reply to: ATM vs Money Changer -rates posted by Bali_love on Monday, 20. June 2011 at 06:42 Bali Time:
The exchange rate you get from ATMs will be mostly determined by your own bank at home, so it's hard to give you a definitive answer.
I always use ATMs - I haven't used money changers since 2003. My credit union charges no fees for using overseas ATMs and the exchange rate has always been basically the same as the recommended PT Central (Kodak) exchange advertised rates, give or take Rp100-200 per dollar.