SSF works fine for me, sure it doesn't play some videos correctly and there's a couple of sound stutters at points, but with a PII X3 710, 2GB of RAM and 4830 512B, things are sweet.
(and before people inevitably jump on me, a) emulators aren't illegal, b) I am using the original CDs and not copies, and c) SSF doesn't require a BIOS to work and as such doesn't come with it, but it's perfectly legal to own the BIOS file for the machine that you own)