I put headers on mine and everything you guys have said is TRUE. It was a project that I had to take the truck into the shop. Broke 2 bolts, had to have the 2 holes oversized and the damn thing blows a gasket on the right side about once a year.
But before you put the header on, make sure they are FLAT(milled, plained, etc) otherwise they will always leak. It would probably be a good idea to, once a month or so get down there and tighten the bolts. Use anti-seize. Have a buddy and a case of beer close by..gonna need help