Ok, I'm at a crossroads. The manual says regular unleaded (87) or higher. However, most all of GM's press releases/engine documents say the for the 2.4 LE5 Ecotec that premium is recommended but not required. Recommended for what? What's the catch? I had to run premium in my old RSX, but that's because it had 11:1 compression. What do you guys run in your 2.4 Bu and why?