In reply to SimonC:
Compared to RISC OS hardware you need a huge range of drivers just to support one model of machine from one manufacture for any period of time due to the constant changes of components.
But ignore drivers, assume you've ported the RISC OS operating system to x86, simulate the situation by deleting every single RISC OS application you own that isn't pure BASIC. Now wait for people to port applications across like they did for 32bit RISC OS on the Iyonix. Wait some more, and more, and more. You'll be waiting until the far side of never, as I don't see any RISC OS developers wanting to completely re-write millions of lines of nice ARM assembler, in to the stinking shambles of the x86 ISA. So you'll still be running all application under emulation, as and the RISC OS is very light weight you wont have gained more than a 5%-10% performance improvement for a huge amount of work and lots of compatibility issues.
But getting back to Virtual Acorn. I'm happy to buy a copy to take RISC OS with me where I have to use a PC, which is at work. But theres no way I'll ever replace native hardware with anything that has to run Windows underneath - why invite that sort of constant hassle and frustration in to your home?