I'm looking to install another shower in my house (mains pressure hot water). In the past   I've installed Mira Excels, Grohe or Hansgrohe thermostatic mixers with a view to having something branded in case of resale.
I've become increasingly sceptical about the pricing on these units - no doubt the mixer valves are of high quality  but the rest of the units, sliders and fascia seem like nothing more than chromed plastic tat.

With that in mind I took a risk on a Bristan Sorrento  and installed it into my own shower room. The slide rail and head had to go (they broke). The fascia and controls seemed more robust than usual however the valve is getting to be more hassle than it is worth. After moving the temperature anything other than the slightest adjustment the mixer wont go back to the desired temperaturewithout a lot of d***ing around.
Is this normal for the Bristan (is the 5 year guarantee worth having if I'm having to break into a wall to return the unit for bench testing).

What do your contributors think about the quality and pricing of the supposedly superior units? Are there any others on the market better for reliability etc?

I've been fitting the Trevi therm for about 10 years, never had a call back.

Excellent company to deal with.