OK let me amend my comments on the Garmin RV890, I finally searched out some advanced training on and found it here:
TechnoRv series on learning the RV890And I have just been scratching the surface of all the large number of capabilities of the unit. I don't think that this series will help all that much until you have used the unit for awhile then this material will greatly enlighten you. But before springing for $400+ you may want to scan thru these videos to see what you are paying for.
Some of my irritations were not being able to search a distant location for some service, cg etc. Well you can. The layout of the screen is also completely customizable. You can rearrange it, add delete functions, add widgets. Search for propane, dunp stations and so on. It even has some sort of boondocking mode which I haven't looked at.