I have been using a IBM Lenovo x220, (3 models in the x series) with the 12.5" HD (1366x768) LED Backlit Display, 2x2 Antenna. Its a personal thing as you will find out, this particular unit has exceeded my expectations and the solid state drive rocks. Super light weight, rugged with a fantastic backlit display.
I have owned others with larger screens, but felt they were taking up to much real-estate. When using a ram mount and/or something similar it still leaves room to spare without jeopardizing any visibility and leaves plenty of room for the passenger so their not crowded (depending on vehicle). Small enough to slide right into my security box. Just a few comments from my past Laptop usage and mistakes............ good luck
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