"All the mods" = POS intake. I'm going to try to hack together the Weapon-R poop that on there with my old Cobb to see how that works. The WR filter is disgustingly dirty.
Well, like I said, I've done almost no maintenance to it yet. I also have plugs waiting to go in (NGK V-Powers) and Magnecor wires on the way. Ran some Subaru Top Engine Cleaner through it this afternoon, and it will get an oil change this week too. If it doesn't pick up after all that, I will do the O2 sensors also. But I think part of the problem is 25-30 minutes at either WOT in 5th, or >60% throttle in 4th gear comming over Donner Summit. The RS used to average ~28 mpg on the return trip over the summit, but I could leave the cruise on in 5th gear the whole time and it would run in closed loop almost the whole way.