Tuning differences

I want to get my Nelson tune but I was wondering what differences would be between a 87, 91, 93 octane tune would be? Is it worth the $.30 a gallon extra? What's the deal with the tow hall race mode.
I drive my truck for work everyday sometimes 3000 miles a week and don't want to go broke buying fuel.

Its worth it to go 93. You get to run much more timing and get better mpg

Thats what i thought just wanted to ask to be sure i was correct

tow haul is only for trans settings. i has no other effect on tune

93 is well worth it

Thanks for the info guy. I need all the help I can get.