Ok I guess its for IGC right, so heres my opinion about cars i drove:
BMW M3 GTR = Good top speed, bad acc, and bad unresponsive handling
Lamborghini Murcielago = Great top speed, Great acc, semi-good handling
Corvette Z06 = Good top speed, Great acc, muscle car handling (bad handling), but IMO its car with best driving experience
Lotus Evora = Great top speed, Good acc (you wont reach top speed easily, but in lower rpm its great), bad-ass handling (but you can easily spin-out)
My pick would be Evora for racing (It's overall better than murcie if you tune it well, and if you can use its advantages over murcie), and Z06 for free roaming (ultra tuned it's just 1 second faster than my ultra tuned escort, but it has better driving experience