Just had a look at virtualbox 1.5.6 might be a beta version that lets you choose any of 3 network cards as default one of them being the E1000 intel.
It also has the IDE controllers of piix3 or piix4 option and runs much better in piix4 over the last VBX1.5.4 I tried last time.
Hopefully they add a few other tweaks in the future.
