Nadsab,
While you may not realize it, you have asked a bunch of different questions.
People that know I have had a job description that said "Navigator" often ask this sort of thing of me.
Navigation has two primary parts.
1 - Knowing where you are.
2 - Determining how to get to where you want to end up.
Most any modern GPS can answer the first question.
If you plan to go hiking in remote areas, any decent handheld will be satisfactory. To this end, you should read reviews and go to real stores and fondle the units. You can also download and read the manual and see if it makes sense to you.
The problem with trying to use a vehicle GPS for this is the short battery life and often batteries are not field replaceable.
The problem with trying to use a hand held unit for street navigation or planning is that they do not easily do many of the required functions and the small screen makes for a difficult time at planning.
As to the second question, a laptop or tablet with an attached GPS running one of the good navigators (Street Alas, Strips & Treets or Coopilot) will both report your position and be of amazing assistance in planning your route to any destination. The map quality of all of these is a continuing issue. If someone says one's maps are more accurate than another's, say "thank you" and go on your way. The best part of these is the road map with a "You are here" arrow.
The computer navigators can also download overlays that contain information that you will hard pressed to otherwise acquire. These are all very powerful packages. They make it very simple to lay out a route and then adjust it for stops, divergences or timing.
Carry a computer also can give you access to on-line data that may affect your route. Or, if your route gets affected by something, changes are simple and transparent.
Remember, Thinking is the least expensive and most reliable thing you can do. Borrow what you can, read all you can. Do not be afraid to admit you made a mistake. (You can always try to sell it off on EB.)
Good Luck
Matt
Matt & Mary Colie
A sailor, his bride and their black dogs (one dear dog is waiting for us at the bridge) going to see some dry places that have Geocaches in a coach made the year we married.