hello, Steve
I cannot give you a sure information since I've never been to Cuba, but I'm leaving ofr Cuba this weekend (hope it is not too late). I've spoken with a lot of people who have been on the isle and almost everybody has told me they brought all cash. I agree with you and find it risky. We've changed 500 $ cash and 300 $ more travellers cheques, and appart of it, we go with a credit. I tell you what it says my Lonely Planet guide: banks tend to be very relaxed at their job, so you, might wait for one hour, but, to tell the truth, I prefer it rather than bringing so much money. So, if we need, we'll change the cheques (you have to show the passport and there is a commission of 3 or 4 %) and maybe we'll use the credit card, too. With Visa and MasterCard you should not buy things, since very few shops do have the machines (I hope you understand me, English is not my mother tongue), but you can rental a car for instance or get money in a bank, showing your passport. But, be careful! They will accept the credit cards, only if they are NOT issued by an US Bank. Be sure so, you have an European credit card and you shouldn't have any other problem rather than the Caribbean relax.

haritz-Thankyou very much for the information,it is most appreciated.

Take lots of $1 US for tips, no bills larger than 20's, take some with you and leave the rest in your hotel safety box. Anything large like trips, use you charge card. American money only accepted.