Yes it is light indeed. One piece and easy to take on and off.
The muffs alone are about 4 Lbs each more or less.
Yes, the lighter the exhaust, the louder it will be but this system perhaps because of the light alloy used is actually quieter. It does have a funny Formula one type of sound though. I liked the thin gauge stainless exhaust note better. The weight difference advantage is what shuts my [BETTER] MOUSE trap off. LOL.