I installed the cutouts on my V8 right after the catalytic converters. The valves work great, they completely change the sound from rowdy to stock in an instant and they don’t leave any sounds lingering with the valves closed. No issues with opening or closing the valves, even in below freezing temperatures in Pennsylvania. The material could be a little thicker but if you know how to weld you can install these. Overall they are a solid purchase. If you have had the idea of buying them floating around like I did, I’d say buy it.
I added a video so y’all can have an example.