tracked my stock 09 WRX right after first oil change at 3600 miles. drove it hard all day (mainly in 4k-redline in 3rd and 4th gear) and then drove it home. I'm at 7100 miles right now and have another track day scheduled in another 3 weekends.
I don't want to say I'm paranoid or confident I don't have the problem, but it seems like there's simply no good early warning signs, so if you want to track your car, track your car. If your engine is going to blow, there's nothing you can do about it. I think after a second hard track day, I'll feel relatively confident about my engine's condition.
And my build date is 07/08, so I have been somewhat holding my breath until I get past the last known mileage for defective motor.