You boys with the M135s are lucky. There's nothing available for the F20 125i to bring it up to 328i power
.
Australian BMW dealers don't have the M PPK available anymore for the F20 125i (bizarrely it was only available for a few months) and there aren't many reputable tuning companies out there offering anything off the shelf for the F20 125i. Most seem offer ridiculous gains for little money and I am hesitant to go down that path..