Hi, I recently got a crazy idea to convert electric baseboard heat to hot water radiant heat. To make a long, complicated story short, can anyone enlighten me on the impossibility or advantages of installing old, cast iron radiators versus installing newer Slant Fin radiators. I've heard the Slant Fins are the least expensive to buy but the most expensive to heat with. I recently purchased some beautiful old radiators but it's tough finding anyone who wants to hook them up in a house that's never had them.