Quote (CarsAndKush @ Dec 6 2014 02:55am)
Is it cheaper to purchase per gallon if you have it available?
depends on your area. It's cheaper than 91 over here but it's a lot better to run for the engine compared to 91, especially on turbo's/superchargers. Only downside is you typically need injectors/tune to run it, there are limited stations where it is available, and worse MPG.