Just about everything being discussed here will show you a route. Turn-by-turn navigation is a bit more than that, and I find it very helpful in avoiding those checks and delays.
"Give me a route" is complex... there are several different ways of getting routes that you want: creating them within the device, creating them yourself on a computer, importing someone else's. I use all of those at different times. Just about everything being discussed here will support all of those.
I haven't heard that described as a problem in practice.
They have lots of tricks to extend battery life, and it's worth working through a fair number of settings to find what's right for you.
I mentioned this with the Edge 1000 because it wouldn't always last a long touring day. but that was an early all-singing all-dancing model, and the ones that i would look at now (upthread) are better.
There are also strongly held opinions on removable and non-removable batteries.
Jonathan