I stayed at Punta Cana Excellence last Christmas and New Years. Nice place and, a tip, the most you should tip at any one time is $1.00, trust me.
As for cigars, yeah, bring your own. I went with nothing in the hopes of scoring big in the cigar capital of the world (outside of Cuba). I did not achive joy and went home empty handed. I also could afford only two cigars while I was down there (a Fuente double corona was $18

)
First, ALL cigars sold in that country in ANY store outside of the factory are about 3 times the cost here in the states. And I didn't find any exceptions, trust me, I looked all over, even in the capital. Nothing, nada, zip ! And yes, be careful of fakes. They are rampant
And second, the main factories of the big boys are about 9 hours from you in the mountains and valleys of Santiago. There are only two ways to get there and neither of them are cheap, a helicopter or a taxi. I believe that if you do make it to the factory, you can get a fairly good deal on a few boxes.
Anyway, enjoy the trip. the weather should be great and the water is fantastic.