I have had name tags that said (Matt - Navigator) and I can tell you that nobody can actually give you a good answer until you tell us what you are driving and what you plan to do with it.
Little dashboard stand-alones are nice to guide a driver, but are almost useless for real planning.
Laptop navigators are great for planning, but are hard for a driver to deal with when underway.
Smartphone apps are kind of like little stand alones, unless you forget to download and store the maps before you lose cell service, then they are not good for much.
Matt