Gaming on the Go: Laptop vs LAN Rig

Being on both the host and attendee side of numerous LAN parties, portability becomes just as important as power. That conundrum, paired with being a full-time student, prompted me to purchase a custom built gaming laptop. My editor, however, took a different route, building a miniature 'LAN rig' the size of a lunchbox. That's when our testing lights flicked on: which is the better solution?