No personal experience in any of these places, but if you pay in Euro, be prepared to get your change in the local currency. Also, smaller shops and restaurants may not take the Euro, although the tourist trap type places would be happy to (at bad rates).

Why not just get what you think you will need out of an ATM? xe.com will give you exchange rates so you can plan what you should need.

http://www.xe.com/

If you are going on a cruise tour, the shops and restaurants you go to will probably have inflated prices. If you can find the 'local' shops and restaurants, chances are the prices will be better, but you may not find anyone who speaks English and credit cards may not be accepted.