We really enjoyed it when we stayed there last year. We prefer state parks and wooded campsites, so MBSP was more to our liking that the other "resorts". I will say that the airstrip did create some noise, but nothing to make us regret our choice. The staff was very friendly, the lots were decent sized (especially compared to the "resorts"), and the beach was just a short walk away in the State Park.
I have also read good things about Huntington Beach State Park a little south of Myrtle Beach.
Hope this helps with your decision.
Doug