I would avoid the multi-jet burners completely. Those burners are designed to be operated at wide open throttle. The air/fuel ratio is not adjustable and that translates to a dirty burn at less than wide open. Yes, they are impressive to look at. High on the bling scale for sure, but in reality, there are better options IMO. I would choose a 6" dia. cast iron ring burner similar to this one: http://www.agrisupply.com/burner-cas...82/cn/5400001/
You can run that burner on high or low pressure gas, but the one shown is set up for low pressure. To run it on high pressure you would need to buy and change out the gas orifice. Not a big deal to do. I would set it up for high pressure and use an adjustable pressure regulator (0-10 psi) to run it. I have one set up that way and it works great. More than sufficient power for a 12 gallon batch.
Now then, inevitably there will be others who disagree with the above and many will defend the multi-jet burners to the death. Asking this question is similar to asking which malt mill to buy. Everyone loves the one they have with only a very rare exception. It's a human nature thing. Brand loyalty I guess or something like that.
I'm also not a fan of the huge hurricane and banjo type burners. They are somewhat better than the wok burners as, at least, you can adjust the air/fuel mixture, but they put out way too much heat IMO and waste too much fuel. They too are impressive to look at and they will work OK for heating an HLT kettle or for boiling wort, but not so good for a direct fired mash tun if that's what you have in mind. The problem with using them for a direct fired mash tun is that even at the lowest flame level they are way too hot.
This is all JMO. I'm sure others will clock in with counter opinions. Whichever burner you finally decide to buy, report back with an honest evaluation, especially if you go with the wok burners.