Ive been noticing for a while a random stutter around the 25-30mph range when the car is about to shift, this during normal acceleration, any ideas?

 

If you're running the z1 fluid switch it out to the redline type f racing fluid. Do a search. There is a wealth of info on here about it.

 

how many miles are on your car? This is the first I've heard of something like this on a TL-S...

 

Or it could be the pressure sensors (a.k.a. solenoids) Do a search on that as well. There is a very informative thread title Interesting Conversation with my Transmission Builder.

I experienced your issue around 20k miles ago (at 110k) and cured it by swapping out the pressure sensors and doing a single drain and fill with Redline ATF.

 

The car has about 45,000 miles. Yes i was thinking it might be the solenoids. The car is still under warranty so I might just take it to the dealership have them look at it.