Test drive both cars, then make a pick on which seems more practical/suitable for your needs. I
would go for the Corvette, but it would be a tough choice. When you drive a car like the Elise, then something bigger and heavier, you can feel the difference and the latter feels significantly more clumsy.
Also, you should keep your options open...There are many other cars you could get, for almost the same price, you could get a new M3