Ok I have on MY05 (04 build) STi.

A few months back, I started getting a noise that seemed to be coming from the front, it sounded like a tyre maybe scraping lightly as it only happened when turning right, was not too concerned.

Then I had my car serviced and the tyres were rotated front to back. The noise then seemed to come from the rear, still mainly whilst turning right.

Recently I have noticed the noise get louder, still seems to be coming from the rear left. It would start around 60-70kms then seemingly disappear until you hit 100kms. The similar noise was still detectable at slow speeds whilst turning right.

Last week, I hat Tein Super Street (Aus Spec) installed and now the noise seems even louder. at 100kms it seems to make a very quick "wha,wha,wha" type noise.

My biggest concern is a diff issue. However I have played with the DCCD, set it to full front, full rear and half way and the noise does not change.
Not sure if this makes a difference.

As the noise seems to be localized to the rear left I am certainly hoping it is a wheel bearing or even better a faulty tyre. It is certainly odd that the noise seems to have increased since the installation of the coilovers.

I cannot see my mechanic until the 23rd, so I am just wanting to see if anyone else has experienced this and what it was.

Oh I am running Bridgestone Potenza G3 tyres too and the car had a full alignment after the installation of the coilovers and the car has 67000kms on the clock.