I prefer ASUS to MSI for many reasons, but it comes down to your personal preference on looks/style and small details. In almost every comparison I've seen between ASUS ROG vs MSI models with identical hardware, the ASUS not only performs better but has better features - fan noise is quieter, cooling is better and evenly distributed (no hot hands, hot keyboard ect), battery life, ect ect... They will both perform almost identically it's just preference. MSI has been praised for their laptop internals being easier to get at also, among other things.
If you have it boiled down to a handful of models you are interested in, google around for reviews and comparisons. Almost every high end gaming laptop has been covered at one time or another and if they are similar enough you can often find VS pages comparing the 2 directly. *Speak of the devil, heres a link with a direct comparison between the original two you were interested in :
http://www.notebookcheck.net/Face-Off-MSI-GT73VR-vs-Asus-G752VS-vs-Alienware-17-R3.173596.0.htmlMy problem is I can't boil it down to the models I want, I kind of just have to research them all -.-
Edit: It's actually funny how closely that comparison page reflects what I wrote... It's the same story just repeated. On these particular rigs the MSI actually performs better, if you are set between the two I'd say go MSI 100% (and I almost always prefer ROG). The MSI scores higher on almost every bench, has a superior display, easy internal access, and a big one, 4k support. Other than that it's the little differences I mentioned - Asus was slightly cooler, MSI had hotspots ect, but it looks like these issues have been mitigated compared to many of the others I've seen where it was LARGE screen/heat/fan noise/ect differences. Here the "issues" are almost not worth mentioning, almost as cool/quiet.. The MSI uses alot more power but who runs these on battery anyways.
If they are close to the same price my vote is for the MSI
🙂