The Anker Soundcore Bluetooth Speaker has been fantastic for me and was around $30.00 when I bought it. I can leave it around 30-40 feet away and still hear the music pretty clearly. Charging is a bit of a hassle, otherwise I don't have any complaints. I do tend to use the dot more just for convenience, so who am I to say which speaker to use. I would say to get the Anker if you go out a lot and prioritize portability or listen to music with a group of friends or in a loud environment in general. But other than that I don't see anything wrong with sticking with the echo.
I got this one from Anker a few years back. Anker makes really good, affordable stuff.
It's small, holds a charge for ages, and the sound is great. Last year I used it for a listening test in a small lecture hall with about 100 students, and it worked perfectly.
I gotcha. Knowing it's a motorhome, I think you should buy a home kit for the plug-and-play radio, which will come with a dock, an antenna and a traditional power plug. Then connect the home kit to any Bluetooth speaker with an Aux jack (like this one). Best setup I can think of that doesn't involve Internet.
If you happen to know the type of radio they have I can tell you exactly what to buy.
I have this one and have zero complaints. Sounds good and gets loud enough I can hear over my machines. Battery life is impressive as well.
Anker Soundcore Bluetooth Speaker with Loud Stereo Sound, Rich Bass, 24-Hour Playtime, 66 ft Bluetooth Range, Built-in Mic. Perfect Portable Wireless Speaker for iPhone, Samsung and More https://www.amazon.com/dp/B016XTADG2/ref=cm_sw_r_cp_api_Wo6MBbK5T480C