I'm sure it has some merit, otherwise they wouldn't be offering it. I don't think it's a matter of really adding much power, as it is with power delivery. You're more likely going to see some better spool as well as smoother power delivery, as opposed to more power.
If you would like to maintain something relatively stockish for a good price, look into Blouch's 19T wheel upgrade.
Also...biggest concern, what are your tuning plans? That's going to play the biggest role here.