An M3 doesn't really compare to a Duster, the M3 can stop and turn! I'd like to see a Duster race a blown E55, now that would be an interesting race...
You can still buy a modern muscle car:
http://www.youtube.com/watch?v=9IOpuGVoyCk&mode=related&search=
The Viper, Mustang, GTO, and Vette are all alive and well. Well except the GTO...