This is a Chinese photinia, which is why it looks so good. The photinia species most commonly planted in Maryland is red tip photinia which gets terrible fungal leaf spots. It has smooth leaf edges, whereas yours has serrated (toothed) edges.
We would recommend pruning lightly. We're not sure what your goal is. Is the photinia too tall, too wide? You are welcome to let us know more specifically, and then we can be of more help.
Prune in spring. You'll get the best response and less chance of leaf spots. It's normal for this shrub to grow up to 15 feet and, if you prune it lower, it will continue to try to reach that high, required periodic pruning. It should be able to handle a hard prune (1/3rd).
However, since it is so healthy and happy, you might want to use that to your advantage and view it more like a small multi-stemmed tree.