It's really hard to tell which ending for New Reno is good. :) Anyway the briefcase itself won't impact the ending of New Reno nor Vault City. The quests that follow its delivery can however. The ending also depends on what you do with Bishop's women as well as with the items that you'll find in the family safe.

Nice, so the delivery should not hurt or help anyone really.

Thanks! I was worried that trading VC technology would mean some kind of war.

Just make sure you don't get greedy while talking with Moore, in Vault City, about the delivery.

He will leave a note inside the briefcase about the deliverer, to Mr. Bishop, otherwise, and he will not be pleased about your demand. One thing is certain, one of you will be resting in Golgotha, soon.

Haha yeah.

I wouldn't be rude to him, plus empathy perk gives it as a hint.
I agreed that the Vault City slavery and rampant racism was kind of shitty so was cool with Moore even if he sounds like a nutjob.