Which lamp would be better? (spoilerish)

[martinuzz]

I just made a Faenorian lamp of the Magi (+5)
It grants the power of magic map, light radius 3, raises Int, Wis and Cha by 5, makes me invisible, and provides resistance to blindness and Nexus.

However, my current lightsource is the Phial of Galadriel.
When I unequip and drop it, I still am 'lucky', according to a potion of self-knowledge, so without it's +4 luck I still avoid death fates.

I could use the invisibility, so I can put on a 2nd ring of extra attacks.
And I could use the +5 on the three stats.

I am thinking of equipping my self made lamp and keeping the Phial of Galadriel in my Home.

However, I don't know if there is some hidden benefit of the Phial that is essential to keeping my player alive (in mid game, I am level 29 now).
Is there?

[AnonymousHero]

No. The only really useful ability of the phial is it's +4 luck.

[Xandor Tik'Roth]

Unless you get Sting and complete the Set...

[AnonymousHero]

Pff. Still useless .

[Xandor Tik'Roth]

True, but it's less useless.

[IckyThingBane]

Can something be less useless while still being useless?