I agree that the ringland issue is rare. However if you do a search on here/IWSTI/WRXforums/clubWRX/IWSTI, you'll see that many people has a squeaking clutch (i.e. making personal testaments to that case), making it a common condition. Whether they treat it as a problem is up to them, and often enough it doesn't have detrimental effects on their car. Those who did bring the car in to the dealer, the dealer was able to find the TOB and pressure plate damaged.