OK Both these guys have serious power and some significant limitations. What it likley comes down to, is the fact that Willard is more durable and has better endurence. I would therfore give it to Willard. Both of these guys are among the weakest linea champions, but neither is even close to being the worst title challenger, or even the worst beltholder.
Well Vitali-Briggs would suggest that Briggs is pretty ****ing durable, and I'd imagine Vitali might hit a bit harder than Willard as well.
Stamina is what he got - it may be about all he's got. But that would be enough. Even a short 12 round champ fight is enough to give Willard the 7-5 edge after Briggs gasses in 4 or 5 - Prehistoric Farmhand by decision.
What leads me to question Briggs durability is is stoppage loss to Darrol Wilson, though I still have an open mind. I would give Willard the ege over Vitally in punch for punch power, if little else.