summer vacation

I have planed to go Amami Oshima in Kagoshima prefecture for this summer vacation because there is my friend's parents' house. But the plan didn't go easily due to some reasons. So I changed my plan to Amami and planed to go Saipan this summer. Last year, I went to Guam for our company trip. It was very humid and hot in Guam as well as Japan. There were many Japanese in Guam and many local people could speak Japanese, in particular some sales talks which are "Irasshaimase(Hello, may I help you?)" or "syageki dou(How about shooting?)" etc. I didn't feel to be resort island. Probably in Saipan, the local will be able to speak Japanese and I maybe don't feel not to be in Japan. However, the cost of the tour to Amami in Japan is almost the same as the cost of the tour to Saipan. Which do you prefer the domestic tour and the overseas travel? I selected to go abroad.