We've had water softners in every house for the last 25+ years... Wouldn't be without one! In that time we've gone through 3 of them; they only seem to last about 7-8 years. Now on our fourth. After LOTS of own end user experience we recently changed to a Plumbsoft Solo from Monarch.
http://www.monarchwater.co.uk/produc...ft-solo-ultra/
Plus points:
Non-electric; though, tbh, we already had electrics at the install point due to replacing a broken unit.
Twin cylinder so constant soft water.
Zero setup
High flow rate so low back pressure
Very good low salt usage (much better than our last unit)
I think it was about £700 off the 'net. Self installed but, assuming you have a suitable location i.e. where the water starts in the house, then it's about half a days labour for a plumber: Heck I fitted ours in less time than that! btw local shop also quoted us c. £1500... I told them to sling their hook!
btw ours is a 4 bed house with two showers, bath, etc...
Expect a 25Kg bag of salt to last at least a month and costs about £7.50. We get 2 months out of a bag.
We have everything plumbed through the softener EXCEPT the outside taps. So that's all toilets, showers, etc...
If you live in a hard water area then a water softener is a must!