Honestly I can't believe this product doesn't have more reviews than it does now. As a Mustang enthusiast, exhaust systems are a big part of the culture of these cars. Off-road inner tubes have been outdated for so long, especially as you get older. Not to mention the smell it gives off and how much more it pollutes the environment. Let's start with the basics. Metal core (stronger than ceramic) Compact size Quality company High quality design and much more reliable (People who use cheap crampons that are out of service know what I mean.) I have long tube heads, tubes Offroad H and Borla Stingers. I shrink wrapped them to tame the system a bit, get rid of the smell and make it friendlier to road pollution. He was on target in every respect. And is it available?! How more people don't buy these is mind boggling. I really wanted a metal core instead of a ceramic core as not only are they more durable but they also tolerate high temperatures better. Oh yes - 200 cells?! It's pretty much free. I'd say the sound has decreased by 10-15%, but I've gained depth of sound, I can drive with the windows down and I don't smell like fuel, and I don't have such a chaotic sound with crackles and pops. It still cracks and cracks, but much less often. Overall I am satisfied with this product! If you are looking for an affordable 2.5 inch metal core cat that is free flowing (200 cells) and made by a reliable company, this is the one I would go for. The compact size is also unrealistic, I don't have much space with long tubes and my car is lowered and these fit.