We bought some JA $ here before leaving and withdrew some from the ATM at the Scotiabank (I have a Scotia account here so no fees). The exchange was slightly better from the ATM, but not enough to make a difference. I used my main CC at the hotels, I don't pay any conversion fees, so that works out well. I also took another CC with a low limit to use, I only actually used it at the Mega Mart in Mo Bay. Cash is much easier, many places require ID when you use a CC. I'm not used to using cash at home, so I found it a bit of a pain to use cash. The ATM's also limit the amount you can take out, one day it would only let me take $25K (Jamaican), another day it was $15K (same ATM)...