At this point in time I think Wlad would stop Tua and Vitali would at least come close to stopping him....both would dominate him I have no worries considering what David Tua is these days.

Tua is a totally different fighter now that he was when he fought Lennox, sure he's still dangerous with 1 punch, but Wlad would never give him a chance to land anything he's just too on his game right now.