I push my STI very hard, typical mileage for me is in the 12-15 range, maybe 17-18 if it's raining, but often less.
In almost 3k miles the oil dipstick is more than 3/4 away from the "fill line" and is still less than 1/4 from the "full" line.
So I don't think I burn very much oil at all, shocking for a Subaru turbo I know.
I was 120% anal during break in, gave it full throttle only once or twice when I needed to get out of the way, almost never exceeded 4k RPM. The first 100 miles I always drove <60mph, and the next 400 I never exceeded 65-70. The last 500 I had a little more fun but I only hit about 5k once or twice, almost never gave it more than 1/2 throttle, and I kept varying RPM's, shifting around and changing speeds, even on the highway.