JIT Emulation of PPC on a 3000Mhz x86 CPU would be approximately equivalent to a 1200 MHz emulated G3 CPU using the PearPC code, as it's supposed to be 40% slower than the host CPU.
This can be achieved when you don't need to emulate the CPU i.e. emulator like ShapeShifter for PPC. 1 GHz Amiga will emulate 600MHz Mac, which is quite acceptable me thinks.
