You can run 89 even 87 just wouldnt recommend going WOT. Still for best MPG 91 is needed. I avg 28 MPG’s on a 300 mile trip. Street is in the 17-18 range, dont think any SRT other than a Skittle can get that.
OP, 23k seems a bit steep if you ask me. I wouldnt pay over 20k.
28mpg is amazing to me lol. I get 22mpg on road trips and average 17mpg mixed driving, my car is bone stock though.