Won't work. That's a flow control valve. You need a pressure regulator. They are often improperly named, and often flow control valves are referred to as pressure regulators or pressure valves. But they only work as a pressure regulator if the other end is in an open system. The kegs your lines go to are closed systems, (except when you are dispensing), so that valve will only control how quickly the kegs rise to the set pressure.
So say you have a primary reg set at 16 PSI. You have 2 lines coming off of it, 1 goes straight to keg 1, line 2 goes through one of these "pressure valves" to keg 2, with the pressure valve turned down very low. If you dispense a beer from both kegs, the pressure will drop momentarily in both as the liquid level drops. Keg 1 will return to 16 PSI in 0.5 seconds, for example. Keg 2 will return to 16 PSI in 2 seconds, or 5 seconds, or 10 seconds, depending on how slow you have the valve set, but no matter what it will always return to 16 PSI, and even if you have the valve set as slow as possible my bet is that the recovery time will be measured in minutes, not hours or days.
