Pretty much if you take all the manufacturers of these systems apart and lay them all together the parts are pretty much the same. The big difference is how they run/function that control board and how it acts.
Hydron spends a lot of money on the stainless steel cabinet which I think could be used in other places or to reduce the price.
"The American Republic will endure until the day Congress discovers it can bribe the public with the public's own money.
- Alexis de Toqueville, 1835