I second, third, ...whatever the recommendation. We recently got MCT Island and have only been through a little bit of Grammar Island, but even at the little bit we have done, we both find it wonderful. As for Beast Academy, we just started 4A this week and DS loves it. I wish the rest of the books would come out faster. I don't know that it is quite the same flavor as MCT, but it is the closest we have ever been to finding the perfect homeschool fit with the two programs.