I too am in the market for a water solution. Right now I'm thinking a softener, a whole house filter, and maybe a reverse osmosis under sink unit.
You are correct in that there's no ratings on CR for softeners, and I've not been able to find any ratings out there in the rest of the world. Whole house and reverse osmosis are fortunately rated on CR.
In my searching, I've encountered lots of folks who have strongly urged me to stay away from both Culligan and Hague. The wife and I talked to Hague, and had them come out to pitch. They wanted $9K for a softener and reverse osmosis unit installed. They also were trying hard to sell us their soap--memories of Amway. We could have gotten a discount, for around $7K if we gave them referrals--more multi level marketing stuff.
The Missouri Attorney General sued Hague a few years ago for their false statements so I'm staying well away. Culligan stuff seems very overpriced, but they do put together very pretty marketing which I suspect is where your money would go.
I've been using Angie's List and BBB to find plumbers, although I tend to weight good reviews on Angie's List much more heavily.
Finding a good, reliable, honest plumber would probably be the key. If they are conscientious, then there's a better chance they will only install good quality, reasonably priced, and reliable products.