We love calzones like the ones we miss from Marchiano's in Philadelphia, but the ones we make at home just aren't the same. They seem to come out too doughy.
Once the pie iron is well seasoned nothing seems to stick to it. After you mix up the pizza dough, it's simply a matter of making a dough sandwich with whatever ingredients you like in between.
While I prefer to cook on some red hot coals, it doesn't seem to matter what kind of heat source you use. An open flame, gas grill or kitchen stove yields the same result.