The 128GB Surface Pro 4 models use perhaps the worst NVMe based SSD in production (link is closest model on Samsung's site, but specs line up with benchmarks) : r/Surface
ASCII.jp:オススメ! 「Surface Pro 4」は“買い”だ!! (3/4)
Samsung SM951-NVMe (256GB) PCIe SSD Review
Windows Pre-install checklist - Full Disk Encryption 6.0