Ok, tested the HP Slate 21 pro as a remote connecting to a Windows 7 laptop server, it worked well the touchscreen was responsive and the interface easy to read and to navigate, it seemed stable and throughout the evening of testing it did not appear to crash, I think it is well worth trying as it provides a 21 inch touchscreen interface for under £300.00.
I still think a 21 inch Android tablet is weird and wouldn’t normally choose to buy it, however as a single purpose Roon remote that is quiet (no spinning disk) quick to boot, it might make sense.
Disclaimer: I work for HP but have no vested interest in the HP Slate, (I run Mac’s)
Russ