I've noticed that recently I see more of the "red heart" tapioca pearls when I cook them for bubble teas at the caffe. I've heard of them, but never saw them until fairly recently. I don't even know if they were the so-called "red heart tapioca".
They don't have different textures or taste, but just have slightly red-ish brown color in the center after they are cooked. I like them.