2 months ago we finally set up our doser, and because of the horror stories we have heard about dozers failing, wiping out tanks, and generally being unreliable, made the decision to get a system that had excellent reports.
So we bought the Vertex Libra doser, using the Fauna products for dosing. We are dosing ALK and CALC only right now with the doser and will finally be adding the MAG online this weekend (using up some old product first).
We tested twice weekly for the last 2 months to get the levels dialed in, and they are amazingly stable now. All corals have responded incredibly well to having consistent ALK levels, which was our biggest issue.
We are also adding the trace elements with the Fauna Ultra Light Balling method.
Good luck with your research. Dosers are like lights, I think. Everyone will have their favourites that work for them.....