Personally, I don't prefer to travel with 7-14 days of USD cash. I would much rather take a private taxi to the Scotia Bank or NCB and withdrawal 3-4 days of cash at a time.
1) I can get JMD, and
2) I usually have to go to the grocery store about the same time I need money, and
3) the ATM fees are actually pretty favorable (unless your bank at home dings you extra).