I think that Watson was better than Benn and arguably Euabank (I reckon he got the better of him first time round... and was on his way second time round till he got hit with those 'Monstor' shots)

and this was when they where both nearer to their primes than when Calzaghe/Colin's beat them.

I can only speculate what would happen if he fought Joe, there are too many styles in this list for me to really make any sort of order.