virtualbox.org

Are there any opinions on which Linux disribution would provide the best performing host for VirtualBox?

Thanks,
Nick

It doesn't matter, they will all perform equally well. Though it does matter how many resources you have left depending on the type of installation. E.g. a headless or non-GUI installation obviously gives you more RAM to provide because the Host doesn't use it. But it makes it harder to manage and use VMs if you don't have a GUI.
Anyway, you're just as good if you install Ubuntu, Fedora, OpenSuSE, Arch or any other distro.