I've dined with Shamu at Sea World in San Antonio. I even made a joke about having fish for dinner that got everyone in line laughing. Anyway, I didn't think it was bad. The food was great. We dined at the beginning of August when the temps were in the 100's during one of their heat waves, so dress appropriate to the weather. It's fun if you have children.
I also recommend the Shamu Rocks Texas show.
A day at the park is what you make it!