computer gps
I had a computer gps, it was the delorme model. it was a small round puck like antenna that opperated via a USB cable. it worked fine exept that you would have to buy updates. However it also allows you to do video capture,print map sections. you can save trips easier and do a lot of other things a hand held cannot do.
If the computer will always be in the truck, I would consider the computer version over a handheld due to the additional functionality if you were going to use it. The computer version will work when not in cell tower range thus its better than your phone. A hand held, may have to be held out the window at times also.
consider what you are using the computer for also. you may can update to a tablet that will give you the a full screen version of your phone but still will only work from cell towers not sat. if you have wifi hotspot on your phone and the tablet can perform the functions you need then dump the lap top and invest in a good tablet
I had my unit quite a few years ago so i would shop them for functionallity not price. if you base it on price, get the handheld.