Hit 3,000km on the break in oil and couldn't resist any longer.. Put in redline 10w30, engine is the 2.2L 4 banger in the 04 Honda S2000. The engine definitely sounds smoother and seems to rev up a bit more freely, all the way to the 8300rpm redline. Still not sure if I'll change this oil before the winter or leave it in while the car is stored.. by then it should have about 6-8K km's on it. I was actually surprised how much noticeable the change in the engine was.. I wonder if it would have been the same with any other group IV/V synthetic.