I ran 87 before tuning because it was the cheapest, and now I've got 89 street and performance tunes because it's not much more expensive ($100 more a year). My race tune is 93 octane (go big or go home) because I won't be using it all of the time, plus it'd be $100's more a year to always fill up with 93. I also find the race tune to be a bit too aggressive for DD usage.
I'm happy with my 89 performance tune (I've tested all tunes on 93 octane gas). From my understanding, DON'T run a 93 octane tune with gas rated under 93 and so on. Your engine will want to combust faster than the gas is able to... or something like that.