What Octane Gasoline is good for Nissan Rogue 2009? How is Costco gas?

[Kash]

The manual says recommended Octane is 87, but with that the engine performance does not seem to be so good. Should I go for 91 Octane ?

Also how is the quality of gas supplied by Costco?

 

[Zhulander]

Higher octane will not increase the performance of your engine at all. It also won't make it smoother or last longer. Just use 87 octane.

Costco's gasoline is, well, just average. After my family got the Costco membership all our cars have been using the Costco gasoline and it is nothing less or more than what we expected.