I try to use the same location whenever possible for two reasons.

1) If I have gasoline issues I know where it came from.
2) The location I use has dedicated pumps for premium instead of a shared pump between the different grades. I don't want a slug of the cheap stuff before I get my premium. The dilution factor is minimum because I always put in a full tank but it make me feel better.

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Wake up every day that would be a start.