I like the idle of both, I love the Legendary 7.3 but I also love the 2003 6.0 Turbo whistle (when stock) how does the 7.3 turbo whistle sound from the cab, when stock. But I don't like that growl of the 6.0 at high rpm, and i love the tone of the 7.3

 

straight pipe the 7.3 and bigger down pipe off the turbo and you should get a really mean sound truck turb whistel will be much louder

 

7.3 is a better engine, 6.0 sounds better