Guitars and Central Heating

[danomess]

Been meaning to post this thread for a while. Have central heating in flat, but am scared to use it in case it does nasty things to my guitars. I have asked for advice localy but got very conflicting answers, ranging from it wont do damage to someone who'se acoustic neck warped'
I know that there are humidifiers on the market; general room ones, guitar case models, soundhole speciality ones etc. Anyone have any experience of problems or lack of, general advice, options etc. I've seen quite a few guitar pics with radiators in background, so I,m guessing most people have them.