Running old software on new hardware is by far the best user experience that I've had. Everything is blazing fast to the point of feeling instantaneous.

Unfortunately it's getting harder and harder to keep things running with various licensing schemes and whatnot. Hell Microsoft even keeps breaking my old Office install with windows 10 updates forcing me to constantly fix it because they want me to update to their office 360 offering. All that said, both the hardware and software stack are getting a little silly even at the low level. You can send a keypress around the world as a data packet faster than you can send it to your monitor now a days.