BMW E60 M5 V10 is just amazing... Eisenmann Race or full RPI exhaust on that sounds heavenly. Or go for a Ferrari 458 with a capristo exhaust system. Lamborghini LP640 with Reiter exhaust system.
Check these out!
[video="youtube;QAlnEtGJcA8"]http://www.youtube.com/watch?v=QAlnEtGJcA8[/video]
[video="youtube;rf4q6muV1cY"]http://www.youtube.com/watch?v=rf4q6muV1cY[/video]
[video="youtube;nLHR7ef48LU"]http://www.youtube.com/watch?v=nLHR7ef48LU[/video]