Given the octane level is the same is it true all gas is relatively equal and the only difference is in the additives that make it burn cleaner for the engine and the environment.

I've been using Chevron for years with their techron additive paying from $2.28 to today's high of $2.65 for 91 octane and I'm curious to know if other brands work the same way for better or worse.

What brands of gas do you use in your X's that you find works the best for you? Feel free to include what you're paying (I know it might be shocking to some).

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- 2005 X5 4.8is: LeMans Blue, Black/Blue Alcantara Leather Interior, Navi, Retractable cargo floor, Rear Side Impact Air Bags
- 2011 335i Sedan: Vermillion Red, Navi, Beige Leather Interior, Harmon Kardon Audio, Fully Loaded
- 2006 330xi Sedan: Titanium Silver, Navi, Dakota Leather, Fully Loaded
- 1987 Yamaha: Virago 700cc