The speed difference if any depends mainly on the natural gas service supply that is provide to our burners.  Typically household service is 1/2 pound.  In this case you would only be able to use our 32 tip multi-jet burners.  But if your location provides 2 pounds of natural gas service, you can get one of our custom natural gas jet burners with your build.  These provide the same great speed as propane jet burners.   See below for more details:
Commercial Cookers
If you are using our Natural Gas Jet burners (125,000 BTUs per jet) that are available on our commercial cookers (40 gal or larger), you can expect the same FAST speeds as listed in our cooker chart.
NOTE:  To utilize our Natural Gas Jet burners, you are required to provide 2 pounds of natural gas service.
Consumer Pots
When utilizing the 32 tip multi-jet natural gas burners (160,000 BTUs) you will achieve the same speed or better, as a standard boiling pot(without our HPC bottom technology) with propane jet burners.
NOTE:  This is when hooked up to the standard household natural gas with 1/2 pound service.
For estimated actual times you can expect to multiply the time to boil from our standard times in this chart by 2 to 2.5.