More important to me than the screen size is the keyboard layout. With most of the 17" widescreen models these days, they have a dedicated number pad over on the right side of the keyboard. As I'm a nerd, I love to have that at the ready for entering in measure numbers, parameters on plugins, etc.

I would also look for an HDMI output on the lappy, as this can get you all the screen you ever care to look at, for a much less expensive outlay than a similarly sized monitor.

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