i called them up yesterday and they said that 409SS was more flexible and they had more success with the customers using that material. the sales person said that it allowed more flex and it would last just as long as 304SS. warpspeed had the very same claims. the only reason budget makes it in 304SS is because of their competitor's pipe (aka cattman). i have read some information posted earlier by others, but wouldn't you get a 304SS pipe if you had the chance? 304SS doesn't break on our applications do they? so what do you guys think? thanks for your answers.