I'm picking up my new S40 tonight so I have a few questions. I did a search and didn't see anything, which surprised me, so I'll have to assume this hasn't been covered. What brands and octane are S40 owners using? I've been a VW owner/enthusiast for years, so I'm familiar with the 1.8T engine, but I'm curious how the 1.9T handles lower grades of gas. Is it a noticeable difference in mileage or performance?