It has induction hardened exhaust seats that will resist exhaust valve recession when used in hard service like a truck that is towing a trailer. It has flows from the factory that are equivalant to other factory castings as it comes with the larger 2.08/174 valves and an unrestricted flat port. It can also be ported more easily to the 280-290cfm range than the 915 or 906. It is also less prone to cracking around the exhaust valve seat than it's predecessor the 902.
In short, a good head for stock to modest performance applications.