Hill Repeat question

Hello everyone,

Lately i have been doing a lot more hill repeats and for the past two weekends while doing hill repeats i noticed that i did not have to go to the small ring, is there different benefits from small ring(spinning more) to big ring(using more strength) ?

For those familiar with Torrey Pines in Del Mar,CA  that's the hill that i am riding it. It's not super steep or super long , but it's a good one to do the repeats. Agree?