This is exactly what my car needed. Idling is noticeable but not loud. It spins beautifully to a medium growl. They don't hum at all and are much more civilized to ride than the welded thrush mufflers I've had before. This money was well spent and gave my muscle car the right balance of sound and comfort. Reviews complaining about the fit are unfair. This is a custom install muffler. If you don't know what you're doing, have them professionally installed. It's a heavy muffler and appears to be well built. The aluminized materials are thick and of good quality. I don't feel like it will rust anytime soon. I would highly recommend it to any vintage car.