I want to upgrade the stock 128 GB SSD to a 250GB Samsung Evo 960 PCIe NVMe SSD? Is it possible? Has anyone else done this and was able to get full speeds of the SSD without any issues?
The 128G drive is SATA -- the larger capacity ones are NVMe. Yes, you can upgrade the drive to the Evo version. You do NOT want the Pro version for a notebook like this -- it uses too much power and will produce too much heat as a result. There's also no point in a high-performance Pro version, as the system isn't designed with 4-lane PCIe access for the NVMe drive (for that you need a large mobile workstation or gaming portable, or a desktop system).