The cheap ones I bought before did not control the water accurately when hot & cold were being used elsewhere in the house. The result - fluctuating temperatures cold showers. With this Hansgrohe unit, no matter what else is going on in the house, I get a constant temperature shower - spot on, problem solved!
The eco drop safety set that the manufacturer recommends should be removed if product is being used with a combination boiler was cracked when product was dismantled to remove part! It’s a plastic part so assume this might occur again if replaced!