I have Furuno 64 mile open array. When I leave the marina, I'll have a look for weather systems in the area. There have been times when we could see some storms with heavy rain that looked discouraging, but when we pull them up on radar, could see that we could thread through and it was clear beyond them. We went between the systems and had clear skies the rest of the day. I can remember a couple times storms moved in but by watching the radar, was able to make it home unscathed, staying in the clear center via radar on a slightly altered course. You don't want to run in fog, but sometimes it just happens. My radar sees everything - birds in the air or water, other vessels, crab trap buoys, coconuts, sea turtles, whatever is in the water. I can run in the fog, cautiously but confident in my equipment keeping me out of trouble. Same deal at night - cautious but confident. I pay close attention to the weather forecast right up until I go out and then I depend on the radar.
My Marlin is the first boat I've had radar on but I've learned to really love it and can't imagine not having it. Satellite weather is a nice tool, but if you had to choose one or the other, radar is like the Swiss army knife of marine electronics.