The kinetic energy of the mass of exhaust gas carries it along the exhaust pipe, and causes a pressure build up ahead of the mass of gas and a partial vacuum behind it. This principle is used in a tuned exhaust system.
Culligan - $2352 ($2053 w/o R/O unit) Culligan Gold Series (10), Good Water Machine. If I were to look at price only, I would go with either the cheaper Ecowater system w/R/O at $2698 or the Culligan system. At almost $4k, the Kinetico system seems greatly over priced.
Just for the purpose of discussion... your Culligan is a 1.5 cu ft softener. IF it was sized correctly for your water conditions and usage a replacement industry standard softener from an online seller would run you under $600 delivered plus the cost of an environmental cover for the control valve.