The valve is a Yorkshire Mistral Maxtwin
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1469 Personally I find them okay - but my house was possibly the last to have them fitted.
Removing radiator is simple. Turn off the valve and screw down the lockshield screw. Drain the radiator either at the other end if there is a fitting - or by loosening the big nut. Take care not to put a strain on the pipes.
There will be a tube from the valve running approx 2 thirds down the bottom of the radiator to deliver the flow. The return is concentric with the tube. Mine are nylon - some are copper. You need to be ready for this when you eventually remove the radiator. If you move the rad away you may be able to unscrew the tube - alternatively move the radiator all the way until it clears.
I remove mine every time I decorate. I have never had a problem - however I did have one valve with a slight crack - took a while to find a second hand replacement.