I am one of those who often makes purchase decisions around the internal power circuitry.
I'm not at my lab desk at the moment (so I cannot report on that stuff), but I'm dragging around an old laptop, a small SBC (used as a general-purpose computer) and a monitor that I was employing earlier in cramped quarters for 40 minutes or so. The laptop is happy with 11.5V but doesn't have problems with 11-18V (9V 600mA will still charge the battery, slowly, during very mild use). The SBC has an NB679 buck converter so it's good for 5.5-28V. The monitor (2200 nits baby!) will accept 7-24V. These are older kit I use for crawling around with, but most of my "normal" equipment likewise has large input tolerances.
Non-normal equipment (used for areas at home where tool loss/damage may occur) mentioned: OLPC XO-1 (great screen, kinda tough, freakin' old), FriendlyElec NanoPC-T4 SBC, FeelGood P7 field monitor (compact with a thick aluminum chassis).