We use our Garmin in the toad. It's sufficient. It's our second Garmin and it works well. As has been stated, most will give some wrong turns, but in the toad, it's not a big deal. In the big rig, we use a laptop and Delorme Street Atlas. So much extra stuff you can load in it, like low overheads, etc. Have been using it and updating it yearly and never been disappointed. We do also use a Trucker's Atlas because most all GPS's ignore truck routes which can be important in a big rig.
We bought a RM7720 for our small B+ when we headed to Alaska. Didn't really have space for laptop to run going down the road. Love the RM. Yes there is a learning curve from the getgo. . . just different from the Garmin. The best feature I like is the trip with multiple stops. You can program in several way points along the way. I haven't found how to do that with the Garmin. . .just one via point there. Also, all saved destinations are listed in a catalog alphabetically. So if I want to go back to someplace I was a year ago, I can look it up quickly by selecting the first letter of the name.
Rarely use maps anymore, but do always keep an up-to-date atlas in each vehicle.
Dale