I'm not really sure because I don't have either the new Asus or MSI. But I bet the AC adapter would be the bottleneck in the MSI if you are running a high end game and charging the battery at the same time (battery would charge slower). Or , overclocking the GPU and using an extreme edition CPU with high utilization and no battery charging.
If you add up the numbers, +30 watts for battery charging room, 180w can be limiting especially with upgrades/overclocking+high utilization. But I haven't seen any results from anybody yet. Somebody needs to plug in a kill-a-watt meter and run a bunch of tests and assume 87% AC adapter efficiency (class "V" efficiency label on these AC adapters means 87% efficient, class"IV" is 85%, class "III" is 84%, class "II" is 82%). So for instance, if 87% efficient, multiply the power consumption of the AC adapter by 0.87 and you'll get the approximate power consumption of the laptop itself.
It's intuition and I think there is a reason why Asus chose a 230w AC adapter and why Alienware chose a 240W AC adapter because they thought it would be useful.
Oh and 1 other limitation of the MSI besides the limited wall power. If you are trying to use the keyboard and the touchpad at the same time, such as if you are gaming with the built in touchpad for some reason, it may shut itself off and you can't choose to keep the touchpad on. Hopefully that issue will be resolved but otherwise it's another reason to go with the Asus.
Neither machine is perfect, and Clevo and Alienware have screen issues; From a review I read, Clevo when on battery power, the screen brightness goes way down. With the Haswell 14" Alienware, the screen brightness is always belows 200nit and very glossy. But I've heard the screen brightness on the 17" Alienware is very good, great speakers, might be a win.
