I havent used the AquaMedic but I know the Milwaukee regulators are susceptible to end of tank dumps. I watched it happen when my last tank ran out, working pressure went from 10psi up to over 40psi and the only thing that kept the tank from being gassed was the pH controllers. The AquaMedic regulators may be susceptible as well but just something to consider with the Milwaukee.
I suppose you noticed that the AM regulator doesn't have a needle/metering valve, solenoid and bubble counter. Also, it has a fixed working pressure instead of adjustable. It is too expensive for what you get with it, IMO.