Which one is more effective?

[esenn1]

It's not a versus thread. I'm asking generally.

a) someone with Sharingan in one eye (with its full capabilities activated) and Rineggan in the other.

b) someone with Rineggan in both of his eyes.

Maybe you say "well, we have already Obito and Madara/Nagato". I don't mean this. Actually Rineggan is the ultimate form of Sharingan, then it should be more powerful than Sharingan. Well, what do you think? is it really so? Is someone with Rineggan in both of his eyes necessarily more powerful than the former (a)?

[DrehVerWortEr]

I think it's Rinnegan/Sharingan, if you can use all Rinneganpowers with one and have the MS that can cast amaterasu (or obitos MS with Kamui)
But i don't know if you can just sum this abilities

[John Lucifer]

i guess
rinnegan is more powerful..
u see pain's power through rinnegan
it was awesome

[Sage of all Shinobi]

Madara: two rinnegan from evolving his Sharingan, has the power of Rinnegan while retaining his Sharingan abilities

Nagato: two rinnegan but both are implanted, has the power of Rinnegan but no Sharingan abilities.

Obito: Sharingan and Rinnegan, has the power of his original sharringan, and the power of Rinnegan

Obviously Madara and Obito is superior to Nagato because of the extra Sharingan abilities.

[★Sir Derp Obito]

The first option

[Crow.]

I'd have to go with the first option.