I've tested it over the full range of serving pressures. It is very easy to use. when wound fully out the beer flows like a fire hose and when wound right in (about 6 to 8 revolutions of the allen key - its based on a thread so infinite settings) there is only a trickle.
these valves are ment for large bars that would have hundreds of meters of line from one end of the bar to the other, so the taps closer to the cellar would be adjusted to suit the taps further away.
With my reg set @ 100kpa, I let my kegs carbonate over a week or so, then just set the reducing valve to give me a flow rate to produce the desired head for each beer style.... obviously highly carbonated beers still need a higher keg pressure and vice versa for some ales. The main reason I went this way was so I could have 4 cheap taps on 4 kegs in my fridge without a spaghetti of beer lines.....
Asher for now....