My central heating system annoys me. There's no overall thermostat, just a control on the boiler marked 1 - 10 and thermostatic valves on al the rads marked 1 - 5. The problem is, depending on the wind direction, outside temp, quarter of the moon, the house is either too hot or too cold.

Are there thermostatic valves that have proper temperature measuring i.e. where I can set a temp in each room and that room always be that temperature (assuming the ambient temps not hotter than that) or am I living in a fantasy world?

Fit a wall mounted thermostat - usually only a simple 2 wire connection jobbie of off/on. I upgraded our thermostat to a timer thermostat so I have it calling for 23 in the morning 20 during the day 22 in the evening and set to 18 overnight. Works well.