[all variants] Alienware 15 r2 hardware support in Ubuntu 16.04 / Modern distros?

We're looking at buying an Alienware 15 r2 laptop for my sister. I have been unable to find a clear answer: How well does it work in Ubuntu 16.04? or is there a better distro for this laptop? (Preferably Debian based.)

Please list all cons and caveats to getting Linux ruing on it.

The hardware configuration we're looking at buying is as follows:

CPU: i7-6700HQ
GPU: NVIDIA® GeForce® GTX 970M with 3GB GDDR5
Default OS: Windows 10 Home 64bit
HHD: 1TB 7200RPM SATA (We're thinking about adding the 128GB M.2 SATA SSD to the configuration as well.)
Wifi + Bluetooth: 1535 802.11ac 2x2 WiFi and Bluetooth 4.1
RAM: 16GB Dual Chael DDR4 at 2133MHz

Thanks!