Modern auto navigation systems are nothing like the yesteryears ones.
I have no experience with the ones that mount in the instrument panel but have a bit with the portable ones that mount on the dashboard.
New, high resolution colour screens performing very well even in direct sunlight. Well, there is always a time that the sun may hit the screen in just the right way (read wrong way) and make viewing difficult but that is relatively easy to deal with by installing a small hood or just slightly turning the unit.
The operation is easy and much less distracting than a laptop. Even viewing is much easier since the units can be mounted almost in the line of sight. Yes, the screens are smaller than an average laptop but the information / maps displayed are optimized for these screens. I would never, ever go back to trying to navigate in the car using a laptop.
Which unit is the best? Well, most of my car nav. experience is with Garmin units. They are excellent but, my brief experiences with Lowrance and Magellan car nav. units indicates to me that they are all on a level.