We had Scott from Low Country Tours and he was the BEST!! The tour was fun and relaxing. He knows a lot about the area, dolphins, and the water conditions. We saw lots of dolphins. We were there in April of this year. Like the earlier poster said, the larger boats can't go out as far in the sound and they can't get as close to the dolphins. It was a little pricy, about $150 for family of 5, but well worth it!!
Have fun! HH is a great resort and the beach house is really nice too. We can't wait to go back this coming April!