Wow.. way to confuse a thread!
first lets get 2 things right,
1) regulators are rated with 2 (relevant) performance parameters - outlet pressure & flow rate. IMO, unless you are boiling the murray river, its the outlet pressure that is more important, standard 2 Kg/hr flow rate does just fine even upto double batch volume. I biabbed a double batch-ish volume, it was super quick.
2) Second, 1 bar = 100 kPa = ~14.5 psi.
Given that, a 205 kPa reg is actually ~ 2bar or ~29psi. That is the beerbelly 'medium pressure regulator' It is also high flow rate.
The other regulator, available from beerbelly as 'low pressure adjustable' reg & from G&G as 'medium pressure' adustable reg is rated 5-15 kPa or 0.05 - 0.15 bar or 0.725 - 2.175 psi. This one is a standard 2Kg/hr regulator.
I'm using the latter, hasn't caused me any trouble. The pressure is effectively up to 5 times that of a bbq reg, which translates into a much hotter flame, better flame spread etc. Brings it all to boil no worries. I start it off at full and then throttle it back to ~ half once its a rolling boil. 1C a minute is easy peasy with ~30-40L of volume.