Consumer Reports did a survey of over 1000 owners of cars ranging from brand new to over 7 years old. This is from their November 1996 issue, page 56:
"Owners of about half the cars reported that they had informally 'tested' their cars to see whether a higher grade of gasoline made a difference. And in more than half of those cars, the owners noticed no difference, as our well-controlled tests bear out. But among those owner-tested cars, 24 percent were thought to perform better on premium, and 14 percent were thought to deliver better fuel economy."
Regarding CR's own testing and results:
"Regular vs. premium. We weren't surprised when the regular versions of the various fuels showed no significant differences in either acceleration or fuel economy. Our tests simply confirmed what we've been saying for the past 60 years: Stick with regular-grade gasoline unless your car owner's manual advises otherwise, or unless your engine knocks--emits an irregular metallic pinging noise."
Oh, and BTW, I'm sure the Corvette's high compression ratio necessitates premium fuel. But of course, if you can afford a 'vette, that shouldn't be a big problem.