I arrived in the DR 6 months ago from Australia. I came here last year on a 'fact finding mission' and vowed then that I would never drive...
On arrival, I decided to give driving a go. I was pleasantly surprised as to how easy it was! I drive daily in Santo Domingo and have driven to the north coast from the capital (via Moca) on several occassions. I have also driven to Constanza which is not to be attempted by the faint hearted (!) and out to Juan Dolio. I am planning to drive to Samana in the not too distant future.
Coming from Australia, I had to learn to drive a left-hand drive car AND drive on the 'wrong side of the road'!... Oh, and I am a woman and we all know what they say about women drivers!!!!
If you are a confident driver, you won't have a problem. Take note of all the advice given as it is extremely relevant. Many of the roads are in extremely poor conditions so you must take this into consideration. The drivers on the roads are inconsiderate, speed and do stupid things. I never cease to be amazed!
Have fun and ENJOY!