I have 2 EPIRB's, a SPOT, and a DeLorme inReach, along with a beacon on the upper deck that automatically goes off if it falls below the water surface.
Safety devices that get put in a ditch bag or stuffed in a drawer are second-rate in my mind unless you're doing far offshore cruising. A much better strategy for coastal cruising is to use devices that you'll actually use every time you're out. Then they're powered, checked to be working, and you'll know exactly how to use them if an emergency ever really happens.
So it's fine to get a PLB. But what makes much more sense, especially if you're really cruising and not just going out for a weekend here and there, is to get a DeLorme inReach. It becomes a satellite messaging system and more importantly, actively tracks your boat as you're moving. This allows friends and family to see where you are by using a variety of websites and tools. If there's an emergency, you can set off the 911/SOS mode and also send a short message about the actual emergency. That is so critical especially when you receive a response knowing that someone is coming.
Contrast that with an EPIRB or PLB. You hit the emergency button and the thing blinks. You have no idea if anyone is receiving the signal. Chances are, the batteries are out of date because you didn't feel like spending the money to update them, thinking they'd last another season. That type of thing never happens when you're using the device every time you go out.
Imagine sitting clinging to debris as your boat is sinking, 10 miles from shore. Do you want to know that someone is coming? Or just hope they are?
So my advice for coastal cruising - if you only want to spend money on one type of device, make it a DeLorme inReach and really use it every time you're out.