Join Date: Apr 2011
Location: CA, United States
Out of those two Milwakee appears to be a much better choice. Milwakee is not a high-end regulator, but at least it is a regulator with adjustable working pressure.
I'd say that one should avoid CO2 regulators with preset non-adjustable working pressure. I have no hands-on experience with American Marine regulator, but the pictures as well as its user manual suggest that this is a non-adjustable design. For this very reason I'd also avoid AquaticLife, Aquatek and Azoo regulators.