It's my first time arriving into Japan not from HKG, so I'm gonna have to change my currency after arrival instead of prior to arrival. I've read through a lot of info that ATM withdrawal is a good deal, and I have a Citi checking account in the US. However, they charge a 3% foreign exchange fee and I wonder if there is a mistake in my calculations that make withdrawing from the ATM seem like a worse option than buying cash at the counter at NRT (I know that the cash rate is 3 yen less for every US dollar):

Suppose the true rate is 1:123, using ATM to get e.g. 72000 yen would cost me ~$585.365...with 3% exchange fee ending up as around $603 in total.

Using the cash rate of 1:120 I would be getting 72000 yen for $600.

I know it's just a nominal difference but is that how it works? If so I'd rather bring cash with me...it saves me the paranoia about the ATM not working or whatsoever too.

Thanks for the help in advance!