MoodleBox is focused on hosting Moodle. This means that you can be sure that the underlying system is always up-to-date and specifically tweaked for Moodle support. Moreover, the MoodleBox plugin is installed out of the box, so you don't need to install it manually.
IIAB is focused on hosting many tools, including, but not specifically, Moodle. There's not specific system tuning for Moodle. It is a great tool, and we share a few same features/issues, including the wifi clients limitation.