Seems to be more of a whole snake than snake oil. From the little I read, you need to get the compatible pump and radiator to get the benefit.

I didn't read anything on the transition characterisitcs. It might take an hour to get to operating temperature... if it ever gets there.

I also didn't see anything on cabin heater effectiveness and compatibility with various climate control systems. It might not be such a popular system if it can't heat the cabin in winter.

Sixto
91 300SE