Shower valves

Is anyone familiar with either Grohe thermostatic valves or Moen Exactemp valves? They have either a single control valve for both flow and temperature or double controls with one for volume and one for temperature control. With the price of these valves has anyone used these valves or can give a recommendation as to which would be a better quality valve to use?
Thanks!

Around here, at least, parts for the Moen would be easier to find. Cartridges for thermostatic vlaves are expensive, but are reliable and should give many years of service.

The Holiday Inn in London, England has Grohe thermostatic valves in their showers...seemed to work fine. I liked it enough to buy one for my home, now a couple of years old. Hope it lasts a very long time.