I don't have a clip, but from others (forums, etc.) I have heard that straight pipes on Mustangs sound pretty bad. I've never personally heard one with straight pipes though.
When i had mine it sounded good on start up, and 1-2 gear. But anytime after that or under a load it sounded like absolute ass, or a big truck with straight pipes.
Yeah, it sounds good when WOT but if you short shift and aren't running a higher than normal RPM it'll sound like absolute ass as stated above. Cruising in 5th was terrible even at 2600 RPM... Just sounded like an old F150. You can really hear it in my 2nd video.