I was recently between laptops for a few weeks (both laptops have 2.5" drive bays), and needed to temporarily use my 2TB Samsung 850 EVO SSD with an older Lenovo Yoga 13, to limp along for a bit. Turns out Windows-to-Go-like behavior is now automatic and easy, even using just Windows 10 Pro. I just put the SATA3 SSD into a USB 3.0 enclosure, hit F12 at boot, and chose the drive to boot from, and it worked fine. Sure, Device Manager found some new stuff, and things were a little slower, but using an UASP type of enclosure made the speeds tolerable for a few weeks.
The thing that stopped working were daily backups, since VEB/Veeam Agent for Windows now saw the C: drive as a Windows to Go USB drive. I've seen requests for support for backing up USB drives, this request is related.
Any plans to offer support for backing up USB devices, particularly when they're in the Windows to Go use case scenario? It would be very helpful, especially given tomorrow's world of USB 3.1 and Thunderbolt drives (and no internal 2.5" drive bays) that could make such scenarios more likely.
I realize this is a rather niche need, figured I'd just ask to see if such a capability is of interest to others too.