Could only get two of those links to work. One to Vibox, the other to G4. Of the two, I would say the G4 would give the better gaming performance. It, at least, has reasonable graphics card, although the Vibox has slightly faster processor, and more storage, which may give it slightly better performance in other areas. The usual health warning, when buying on ebay: do check out customer reviews, for how seller deals with any problems.
Bear in mind these are BUDGET gamers. You can't expect high frame rates, at high settings, in all games.