17-inch displays are massive energy sappers, but thanks to the large displays, manufacturers can also fit larger batteries. In our battery test, both the MSI G70 Stealth and Razer Blade Pro managed well enough, clocking around two and a half hours in our a battery tests. The Blade Pro managed 163 minutes, 12 minutes more than the GS70 Stealth, but then it has a significantly larger battery - 74Wh vs. 60Wh.
In terms of actual power consumption, we found the GS70 Stealth to be more frugal than the Razer Blade. Its power draw of 23.84W is actually lower than even the smaller Razer Blade and Aftershock XG13. The Blade Pro recorded 28.83W and this could have been due to its SwitchBlade UI, which is really a second display.
Our Portability Index factors in battery life, weight and volume so you can see which notebook is the most worthwhile to carry around - the higher figure, the better. Both notebooks ranked quite similarly, with the MSI GS70 Stealth netting a slightly better ratio - 0.361 vs. 0.325. On the upside, this is significant better than the scores achieved by other hulking 17-inch gaming notebooks such as the MSI GT70, Alienware M17X R4 and ASUS G75VW. In fact, they can rival smaller multimedia notebooks like the HP Pavilion dv6, Lenovo IdeaPad Y500 and others. If it's outright portability you are after for a gaming machine, the new 14-inch Razer Blade is tough to beat.