96 summoning, and 75 defense would be preferred.
At 96, the iron titan gains you defensive exp, while the steel titan gains you ranged exp.
It would be useless to use it because it would slowly ruin your account.
And 75 defense is all you need because in solo pvp you could wreak lower leveled accounts with your dfs special attack.
Nobody would want to fight you and you'll get very few fights.
I can see the logic where that account would totally obliterate PvP, but it would get boring in the long run.