Smallframe- which gear up kit

Runnin polini 130 with standard et3/primmy primary drive of 2:54.

Am I correct in saying : 2.56 with zirri short 4th box or alternatively a 2.86 with the standard box.

zirri box is too dear for me, so is the 2.86 going to make a noticeable improvement to get the best power delivery.

I need an answer to this prior to purchase.


I personally like 22/63 (2.86:1) combination.
So I would go for it.
But we could have different tastes…