I have an EPIRB on the Clara Mae. I installed it for my trip with my youngest daughter last August which included a couple of extended open water runs.
My opinion is that if you are going to spend any time off shore, an EPIRB should be standard equipment in spite of their cost. Most folks don't realize that when you are swamped or capsize, the boat's batteries typically discharge in short order. Not to mention the fact that if you are caught in weather strong enough to swamp your boat, it will likely be all you can do to hang on with the rocking and rolling going on.
Years ago I spent a few unplanned days and nights in the water off shore in the Gulf of Mexico. Even though the Coast Guard knew we were over due the first day, it took them several days more to find us. That was several days and nights of rough seas, swallowing salt water, sea sickness, chemical burns from the boat's submerged fuel tank, exposure, etc. Had EPIRB's been available then and we had one, I could have been home for dinner the first night.
Michael