AEON ATMs don't "waive" the 150 baht withdrawal fee charged by the Thai banks. They simply don't charge it at all and never have, because, as LSM pointed out above, they're not a Thai bank but rather the Thai arm of a Japanese-based credit card company that operates regular ATM machines in many parts of Thailand.
Their ATMs normally will work with any VISA or MC-logo debit card. But some straight ATM-only (non-VISA or MC) cards will not work with AEON ATMs.
If you ever had a problem withdrawing cash from an AEON ATM, like the bills aren't produced or come out in the wrong amount, their ATMs typically have a sticker on the front with a Thailand phone number to call for customer service from AEON. But in my experience, AEON ATMs are mechanically at least as reliable as any other Thai bank's machines.
Again, in my experience, where you're likely to have more problems with any ATM is where it's a standalone unit and not located as part of a bank branch or, in AEON's case, an AEON office. It's the standalone ones that seem to have more problems either with a] people messing with them and/or b] the machine owner not monitoring and maintaining them especially well.
Edited by TallGuyJohninBKK, 2012-12-20 14:57:03.