Hey ! It's really hard to theory craft the damage comparison between both because they have similarities and difference. My thought would be that if the enemy team is rather squishy, go titanic or hullbreaker 4th. If they have so much tanks that yo ufeel like more damages are needed, then you can go for another on-hit item on 4th. At least that's what i currently do. You can check my main account to have an idea of what I currently build ! :)

Thx for your kind message i appreciate a lot :)

My pleasure ! :)