My first big block four speed was 7 years old and had burned out glass packs with no packing left when I bought it. I was 16 years old and I thought it sounded perfect. From 3,000 up, it would sing. My best friend could hear me coming from blocks away as he waited to be picked up for night of partying. They were in effect, straight pipes with only one issue. At a certain rpm, the perforated tubes inside would rattle. The previous owner was an adult who loved the car, so straight pipes were not an issue. Me, I couldn't leave it alone. A Judge recommended that I should have OEM mufflers, so I bought Hemi mufflers. I noticed fewer tickets and came to the opinion: a quiet car has more to offer in sound and feels faster to me.
All that to recommend these for the sound of glass packs, but with longevity: