Gary, those are all things that I had look into before doing this, if I went with a mandrel 1 piece I had to have the pipe flatten out on the top which resulted in a loss in flow. When we built this piece I want something that would out flow everything else out there. As far a sanding the welds I have always felt that was hiding crappy welding. I personally love the look of a hand fabricated piece provided the welding is very high quality. When guys get this piece in hand you will see that the welds look just as nice from the inside, and i bet the other ones out there out there can't say that.