Stoptech ST-40 is on the car now. As my friend said while helping me bleed my brakes, "the pedal is now harder than a 13-year old on viagra". Funny guy, but the engine was off so there was no vacuum assist on the pedal lol.
Despite that, pedal feeling IS amazing. I feel I have a lot wider range of modulation than I did before over about an inch of brake pedal travel. Of course, the stainless lines and master cylinder brace all help with that -- but there's a noticeable improvement over the stock 4-pot setup. My only complaint is that this kit makes the rear 2-pots look tiny!! :P
I'm using the Stoptech street pads for now and haven't bedded them yet as the instructions say to wear off the zinc plating first, but already stopping distance is pretty good.
For the track, I have a set of carbon-kevlar KFP Gold pads that have a mu of 0.47. I'll be swapping those in before track days to conserve brake pads. I bought them from Peter Hanson and they came with a free pass to one of his full-day driving schools - sick deal!!
As a reference, the ST-40 rotors are 328x28mm and stock STI Brembos are 326x30mm. I went with the ST-40 kit since Stoptech claims that the calipers are designed to maintain the stock brake bias.
Big thanks to Chris @ Touge Tuning for hooking me up with a great deal :D