I don't think there will be many updates at this point, I really like the car, and my radio is barely on. Honestly, the car is just plain running good, and most days I forget it's got 300/350+, and I drive it like an old man/daddy-mobile. Just been doing basic oil and tranny fluid changes, and have just over 20k miles on the odometer. That being said, I LOVE hanging out the tail on some of our back-roads a bit when it snows. The only item that is still on the potential list is a break update, but I don't think that's actually necessary with how I drive.
I've have noticed one thing (I'll explain later in the post) that I haven't quite tracked down, but it's so sporadic that I can barely replicate it, and it's more annoying than anything.
I was talking to someone else about the build who owns an STi, and after driving the STi, I think I should have probably gotten one. With the WRX, the only negative I can think of is that the power level I'm at is really too much for the rear diff, in my opinion. I am constantly spinning the rear tires under heavy acceleration in 1st and 2nd, and sometimes even 3rd gear, so the car acts a lot like a FWD car with RWD assist. I had a MS3 with goofy HP, so I don't really like that feeling. Driving a friends comparably modified STi, and he didn't have the same issues. So, if I had to do it again, I might have left the headers & uppipe off and called it a day at TP stage 3 for the WRX, or gotten the STi for past that power level.
The only real mechanical 'issue' I've had is a very sporadic issue, which seems to come in the cold weather only, and for which I can't pin-point the problem. Basically, if I'm cruising in a gear at steady RPMS, once in a while (maybe 2 or 3% of the time, so definitely no where near the majority of the time) the car won't smash into full boost (20+ PSI) when I go full throttle, but instead sort of slowly builds to about 12 psi before holding there. Usually, the car (no matter the gear) boosts to 20+psi pretty quickly, and to 0 psi almost instantaneously. At first I thought I had a boost leak, but its so sporadic/not constant that I don't believe this could be the problem (I still cleaned and inspected the entire system to be sure, but it boosts great almost all the time, so I don't think this is the issue). I next thought it was the TC limiting torque because of wheel slip, but I can get it to replicate the issue with TC off. I don't think the non-defeatable VDC system could do this, so now, I'm a bit stumped. The EBCS seems to be working fine (I can hear it sometimes), as is the BPV from what I can tell, so I don't know. I logged a run in 4th when it happened, and it just boosted to 12.5 psi without any other noticeable issues.
I don't remember it doing this when it was warm out, and the last few weeks have been excessively cold, so I am currently thinking that one of those two (EBCS or BPV) could have frozen up/are sticking as they are in the direct cold air stream from the hood-scoop, but honestly I have no clue. I'll probably clean then out again once I get a few minutes in the garage.