Have SH3 with Win 8.1, no issues after some trial and error and reading some of the threads here
For example not installing in the Programs Folder, running the compatability option with 8.1 so SH3 would run under the Win XP, Service Pack 3 option.
It is on a new laptop I recently purchased. I7 Processor, 8Gigs of RAM and a 2Gig Video Card. My old computer was close to eight years old so it was time for an upgrade, and I went for a mid-range system.