I presume you mean 'burnt out' FCUs, not the spur (cable), presumably due to the fuse/holder (or maybe a 'loose connection')?
So, attempting to 'drill down' to what it actually is that concerns you, it sounds as if it's probably the 13A fuse (and holder), whether in a plug or an FCU is it? If so, I can understand your concern, given the number of people who seem to have that problem - albeit it's usually the high loading of a double socket (e.g. with WM + dryer) that gets blamed.
Kind Regards, John