I was kind of surprised not to see BP on that list also. I remember back in the 70's if you wanted the best unleaded hi-test, you went for amoco white 93.
Mine is used to a steady diet of shell 93 with a side of bp 93. Those are the easiest stations for me to stumble upon. The last time I pulled my plenum I don't remember if any thing jumped out at me though. I was in a hurry, chasing a 61 DTC just the weekend before Carlisle 07. I guess I should have taken the time to look. I remember when I did my R/C's back in late 05 there was a pretty good mess going on in the secondaries, yuck! That was on the original owner's dime as I only had the car for 3k miles at that point.