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.
I'm really surprised at the (high) cost of the Kinetico/Ecowater/Culligan water softeners. Our household is at a crossroads now as our 26+ year old water softener has a stuck brine valve, and I've called the local water softener dealer who is also a Kinetico dealer.