edwants2dive
Glowstick
So if medical care and such is a big concern then I would stay from the DR. They are still 3rd world. Bonaire however is considered second world but it is very close to first world IMHO. I have not been to the Cayman Islands yet but from my research and talking to folks at my LDS the cost would be similar. Cayman may even be a little more expensive over all. The advantage i would give Bonaire is the sheer number of dive sites. I did 22 dives in the week we were there and each different site had something unique to it. Even the multiple dives at Buddy Dive's house reef where we stayed were different each time ( and reasonably shallow if you want). It's your $$ spend it how you want. I wish you safe travels and diving.