X pipe vs H pipe

The idea of the X is to scavenge to exhaust as to what the older American race cars once did by crossing the headers as 1 into 3, 2 into 4 etc. Just two days ago I spoke with a muffler dude who told me this didn't work which to me was pure BS, also said I should rid my car of the supertrapps and change to something better.

Oh well, I'm not one to take advice from those who only think they know.. Yet I think 412 Stroker hit the nail on the head