If you spare him then the sole survivor is technically immortal.

I actually let him out, and when i realised he wanted to kill Jack, I tried to kill him and then got killed myself, resulting to me then killing him with the zeta radiation.

Killed him, way too insane and powerful to let loose on the wastes

He’s a bit of a dick, killed him

As a morals question I let him die. He's a psycho so yeah, no good. Let him live once as part of a vampire mod made him out as the elder vampire of a specific clan. Was an interesting play through. Want to let him live without that mod enabled just to see the vanilla story progression. Would have to be more of a bad guy playthrough though, or at least not that 'ting-good' with the morals.

I wanted his coat though Cabots lab coat was tempting

I released him because his family irked me, and he hadn’t done anything to me, so the decision was made

I just felt like killing him for no reason.

Lorenzo is the GOAT

I set him free because I was role playing as a maniacal psychopath for my first game.