VirtualBox on performance

I know virtualization with VMWare Player on a slow machine is a pain. I was a bit curious about how VirtualBox flares. I loaded it on my AMD Sempron 2400+ machine, and run a copy of Windows Vista Business Edition on a Windows XP host. To my surprise, it runs very well. Okay, I am not running anything heavy. Vista only configure with bare minimum software. The machine ran as it was natively. In fact, it even runs better than my work machine (P4 2.8GHz, 2GB memory) with Windows XP on it (it loaded with all these craps insisted by C&IT service). I am very please with VirtualBox experience. VMWare may work better if it got hardware support, otherwise, to me, it seems VirtualBox performs better with "normal" machines. By the way, I am a fan of AMD processors, as Windows runs much more smoother on them (I know, Intel processors are faster, but I can swear, Windows runs much more smoother on AMD processors, i.e. less lags)