Given your needs, I would say the Perf tune. If you are doing mostly freeway driving of course the race tune could suit you as well, but... i am assuming you spend a certain amount of freeway time in bumper to bumper traffic. I think the perf tune will give you better stop and go mpg than the race tune, especially with the differences in low end throttle and the fact that the race tune holds shifts much longer, even at a crawl.
...of course you could always have the race shifts softened up - thats what I did since I do more around town / short highway runs
2011 Mustang 3.7L V6 Premium ∙ MCA (203A)
Ingot Silver ∙ Charcoal Black ∙ Auto
HIDs ∙ Security ∙ Comfort Package ∙ Remote Start
Koni STR.T shocks/struts ∙ Roush DUB springs