I like to share major problem I found my m80 grills. Grills are starts to rattling from the middle to the top after 6 months old. I remembered removing the grills about 5 times since I have them. It very flimsy made. Soft and very flexible.
I notice the rattling noise when I watch Transformer movie at the beginning scene when the chopter frying over the desert. Another movie is the Master of the Commander by Russell Crow. The cannons going off during the last scene of the movie. I now have double side M3 tapped from middle of the grills to the top across the grills.
