http://www.rosepoint.com/ uses Nerves under the hood on its marine navigation products (so, real-world results). Garth (CEO) did a presentation a year ago or so where he said his entire industry is java-driven and was skeptical about his decision to go Nerves but after testing it on some realtime data for a month and seeing absolutely zero memory leaks or any faults (and relatively low CPU usage), he decided to go forward with it and has been pretty happy with it so far.
I assumed between that and the fault tolerant nature of the architecture that it would be ideal for a standalone device that would be harder to service. I remember doing specs for in vehicle systems in college and the "what if it crashes" question was a nightmare.
