My brother in law had the bullet mufflers installed and ran with muffler deletes. Funny thing is, he said running the bullet muffler along with the delete pipes was quieter than the spintech mufflers. He actually liked running the delete pipes with the bullet mufflers. Said it was quiet at cruising and gave a nice WOT sound. I've thought of doing that with my V6, but I live in california, and all officers around here hate noise.
2006 Ford Mustang V6 Pony Package (Sally)
2005 Ford Five Hundred SEL
1986 Ford Bronco XLT (Papa)