What about Zerex G-05 coolant by valvoline? I was told that it is just as good as BMW coolant by a local indie. I understand his opinion was a bit bias since he uses it exclusively in his shop. But I did some research and it seems legit...have you guys heard anything about G-05? Any opinions? It says that it is only formulated for certain car makes, and generally newer car models. My X happens to fall into this catagory ('01 4.4). Mercedes has been using G-05 exclusively for 20 years. Im curious to know what others have heard about this coolant