I have taken a look at the Master Water web site. The equipment they offer is comprised of much the same equipment available to most everyone on the market. They seem to use their own treatment names but those are the same treatments offered by most everyone in the water treatment business.
Viewing the control valves offered by Master, it appears they maybe clones of other brands but may not have the same quality, life expectancy or parts availability as the high quality brands they are copying (Clack, Fleck & Autotrol).
First off, you should obtain your own comprehensive water analysis to identify the conditions which require treatment. While you know your water has a pH of 5.5, is your water 3 grains hard, 10, 30 or 100 grains? The amount of hardness will influence the size of softener required.
If your water is supplied by the town or a water company, it will have been already tested so a report should be available by only asking. If your water comes from your own private well, you are responsible for monitoring the water's safety so you will need to obtain testing through a lab. Some local universities will perform testing or you could contact your state's agricultural extension office for recommendations on a local lab to use.
Once you obtain a report, post the results here to obtain unbiased recommendations on appropriate treatment methods and equipment required.