Ok. I've done a little writeup on this subject on one of these boards, just can't remember which.
Anyways, the jist of it was that the gap recommended by Cobb (0.026-0.028") was specifically for the Densos. This gap does not apply to any other plug. Reason being is that Densos are the only brand that makes a 0.4mm center electrode. NGK and most others use a 0.6mm center electrode. Because of this they all have different recommended gaps, most non-Densos being fairly close to each other. Densos should come 0.035" out of the box, whereas NGKs should come 0.044", my Autolites came in at 0.050". Using my previous post as a guide, you can adjust from there.
As far as power goes, I doubt there are too many people making 75-100HP above stock. I also find it hard to believe that any plug swap will make any meaningful additional power. The exception to that is if the ones being replaced are FUBAR, which considering your car is at most 1 year old and came with OEM iridium plugs, I doubt. Possible, but not likely, but even then, you won't MAKE power, you just lose less.
FWIW, I'm running a CP-E catted DP, ETS TMIC and Cobb SRI. I switched to -1 colder Autolite XP Iridiums on a recommendation when I used to have the AP because I am/was seeing knock. Can't quite say whether the plugs quelled any of the knock, but I can say for certain that I've learned that my knock is 100% tied to ambient temps. >90degF and I guarantee knock. If/when these plugs foul, I will replace them with the OEMs I took out.