they are so cheap because they are cheaply made. maybe they dont have the "50,000 a year welder.....buy more in bulk......etc.... when it comes down to it....a manifold is just a manifiold. yes mine does have some weld boogers and isnt "perfect". but it shines...and looks ok. it is a tubular design so that limits the welds that could potentially break. i cant bend it by hand....and everything is double tig welded. inside and out. so it is not made out of plastic or anything. it still is made out of metal..which is held by welds. every manifiold is like that.