I am really glad to see this report. I have an 09 Outback 2.5i Limited. It has the 4 cylinder engine N/A. I have been using T6 for about a year now I guess. I do 30,000+ miles a year 90%+ highway. Glad to see this oil holding up so well. I am almost out of warranty so I think I will try to go 10K OCI's with this oil. Do you all think that would be warranted or just stick with the 7500?