I used to use an ASUS laptop - don't recall the model, but it was a monster machine with 16 GB of memory, 2 300 GB hard drives and an i7 CPU.
It bit the dust after 4 years - but worked GREAT with Sonar. Had a 17" screen too.
I just looked at your specs - looks like an updated version of the same kind of laptop I had.
This laptop will have ZERO problems running Sonar X3. It has plenty of memory, plenty of storage - plus having 2 separate drives will greatly assist performance, and it has a great i7 CPU.
I CAN tell you that you will need to go through all kinds of bloatware and get rid of it all, when you first get it. They load these up with all kinds of extra utilities and free trials and just a giant bunch of gick.
I would not advise using the battery much on this, as it will suck the life out of its batteries when you have everything up and running at 100%. Using the battery sparingly will help it last longer and save you money from having to replace the battery pack. (it was pretty pricey for a replacement for the one I had)
I also recommend you configure the laptop to never go into sleep/hibernation, and do not let it selectively suspend USB devices. I also suggest setting the minimum processor state at 100%.
FABULOUS laptop - you will like it, once you clean off the crap and get it configured. The one I had was actually quite slow until I went in and deleted all the unnecessary software utilities and such.
Oh - I suggest you check for BIOS updates and driver updates manually, when you get it, rather than rely on some generic updater software utility. I have seen too many times where those either fail to find a needed and available update, or they update something incorrectly.
Lastly - I happen to Avast's free version of their antivirus software. The laptop will come with some 30-day trial for Norton or MacAfee or whatever. I always get rid of those and use Avast. It is free and your registration will be good for a year - then you simply register again. It WILL by default add some functionality I myself choose to not install - Grimer Fighter, Browser Cleanup, and something called Updater (one of those update all your software utilities). It will also attempt to steer you into a paid upgrade - I always just stick to the basic free edition, and it works great.
Anyways, Good luck - GREAT laptop
Bob Bone