Like many others, I have noticed issues with the brakes on my 2006 STI
in the wet.

The first Winter, I noticed a several second delay between brake
application and any stopping power in cold rain, if you did not touch
the brakes for 10 min. or so.

Last Winter, that issue changed to include a strong pull to the left
when the brakes finally did come on and a similar feeling, sometimes
right after you started driving, if it was wet, even if you parked
inside. I also noticed in the dry, the braking power seems reduced,
or at least the initial bite of the brakes is reduced and I may be
detecting a little bit of fade. Once last Winter, the brakes stuck so
hard after being parked inside wet, I had to rev it a bit and dump the
clutch in the reverse to get it moving. I also noticed that warm rain
now causes the problem too.

When I took the snows off, I noticed that the left rear pads were worn
more than the right rear (still plenty of pad on all 4 corners though,
at 22k) and the clip on top of the caliper that holds the pads was
crooked and not secure properly with the 2 clips that you slide to one
side. At that point, I showed it to the dealer. They found nothing,
but the clip is now straight. (although several weeks later, when I
first looked at it, I noticed that one of the sliding clips that hold
the clip on is not in the right position) The issue still remains.
With one or two exceptions, nobody has said anything about a pull.

Any ideas about what I should do next?