[Richbot]

I've never gone that short so I can't cant comment first hand, but on the 6MT which really would benefit from a significantly shorter 3rd/4th gear gear in most track situations, I think it'd improve the car especially in <60mph corners. Shortest rear I've run was the 295/30-18 Hoosier which was 25.3" but that's so far away from what we're talking about I'm not sure it's relevant, it's not like I was tooling around town on that tire

On the street, only you can decide if it's worth it, but I'd think you'd just change your shift patterns a bit and never notice until you're cruising on the highway a couple hundred rpm higher than you used to. The tire tread and construction will make a way bigger impact on whether you can stand it from a noise/harshness/rain performance standpoint than what size you're on IMO

I know there are plenty of people who have used this size on this car with good results it's not like you're blazing any trails if that's what you're worried about