Starting to buy new baking pans. I've been cooking mostly with metal pans but have some glass. I have a friend that does all her baking that she sells on her business route in glass pans. I thought glass was the poorest of heat conductors. Is this correct. Right now, all my pans are cheap tin type pans that some seem to even show rust if water stands in them. Any recommendations for pans to make bars/coffee cakes in.

On the subject of butter vs. margarine. I know margarine is made up of some water. This friend always uses margarine instead of butter. Isn't this sacrificing taste and quality? She can no longer bake because of health reasons and giving me all her customers. I want to make as good a product as possible. I always use butter in my brownies and cookies. Does using butter in cookies make a different type cookie compared to using shortening or margarine. What's your preference in baking -- butter, margarine or shortening.

butter,butter,butter.
glass is real good for coffee cake.
so is tin.
so is teflon.
so is alum.
so is steel or cast iron.
it's what you like to work with
good luck