John:
I couldn't think of anything I could actually do with my Sinclair even when it was new... even with extra RAM... The Heathkit H-8 was much better...
An XP machine is fine for JMRI and the RR if that's what you have and a reduced chance replacing it... I know of a couple in the circle of MRRing friends.
And yes I still have my Sinclair...
Jim Albanowski