I'm trying this VBox with 2 CPU's working in WindoZe guest.
Nested Paging: Enabled
As expected, I can't notice any difference using guest OS with 1 CPU or 2 CPU's.
Also, the CPUs usage remains real low.
When there's just Linux host, KDE, VirtualBox, and Windoze2K guest running, the CPU usage reported by kima gets as low as 0% or 1%, for BOTH CPU's.