What is better overall: a propane run car, or one run on CH4?

Question

I hear that Methane is better in many ways but the conversion components are far more expensive. Overall, which is better? What would you use if you were to convert your car over to another fuel type?

Answer 1

"better"?   As you say, methane conversion costs more because it is a gas and is not easily liquified at room temperature, so requires ground based compressors and high strength tanks compared to propane.  Not having a farm, the chances of my getting methane are minute and propane is almost everywhere - makes that choice simple.