I've always been interested in one of these instruments and I'm thinking of
getting one to check Temperature / Humidity readings. I operate an AWS and
know the sensors I have are high quality and reliable etc but its always
nice to have a back up and/or be able to verify the data. Also with this
type of instrument you get an instantaneous reading, (I still have my RH
Slide rule!) I would be interested to know peoples experiences using a
Whirling Hygrometer. I've heard various stories/comments over the years
about the idea of 'slinging' 2 glass thermometers around your heard on a
wood/plastic frame can/does have its problems (How sturdy are they against
breakage etc) but if they give you accurate data then it may be worth
getting one.

Best Wishes

Richard
Horsham AWS
West Sussex