I heard from a friend that works at a tuner shop that the correct way, or atleast the safest/fastest way to launch my wrx is to rev it up to around 4k RPM, and then slip it about 5 or 6 feet, atleast enough to get it rolling good, and then quickly slip it out, and if you do it right, the tires spin, and you take off under boost. The concept is that you are burning up your tires, and they absorb the shock and wear instead of the clutch or rest of the driveline. I asked this same question on wrxforum.com, but was not satisfied with what they had to say. I trust you guys a little more. It seems like back when I was looking at buying a wrx back when they came out, this technique was standard, but I haven't seen anything about it as of yet.