Just Blew 2 Head Gaskets at Once. First Run

This is what I have found. I pulled the heads, and two cylinders on the drivers side and one cylinder on the passenger side had blown the head gasket out into the valley. I took the heads to a machine shop and told them to check them out in all the ways possible. They milled the heads due to the slight rough milling that the heads had on them. Then the news....the intake edge of the heads was .005 lower than the rest of the head surface. They had to mill about .007 to flatten the heads. This very well could be what my problem was. You just never know what you will find. Thanks again for the help guys.