I was in the same predicament a few months back. I eventually chose to go with a device sold by Thork Racing, a T665, basically a rugged flexible Navigation device, which looks like a phone and can be used as a phone. There's loads of rugged androids out there, but I found there was always a compromise, mainly lack of NITS (brightness), charging and mounting. I'm very pleased with the T665 so far, very solid device and the magnetic/clip/charging mount is excellent. I also added a button controller enabling map panning, zoom in/out, which works a bit different depending on which app you're using, but a very practical feature.
I plan all my routes in MRA and export to a navigation app I wish to use (the real advantage of an Android Platform). A key point is that I tend to follow tracks using this method, which doesn't suit some riders.
Typically the nav apps I use is BMW Connected, DMD2 (I'm still trialling and really like the UI and functionality; so far so good) and really trying hard to like MRA Navigation. Perhaps it's my eyes, but I do struggle with the blues and lack of other colours which is found in other apps. However, you use the latter the interface between planning and navigation is seamless. There's some excellent training YouTube vids by Serge and Corjan
Good luck with your decision