I have an Oregon Scientific setup with wi-fi feed to the 'pooter. The sensors (wind direction/speed, Baro, Ext temp, Humidity, and rainfall are solar powered and the indications on-screen are pretty complex and colourful!!
Accuracy??... just as good as the awful Met Office offerings on the Beeb

in other words, irrelevant. The displayed values certainly indicate RELATIVE variations but are not necessarily specifically accurate.
This particular unit was a present from a friend for whom I worked part-time and was retail priced at £300.00. They can be obtained for less but I would not recommend them (or any of the clones) as a definitive source of weather forecasts - but, neither would I recommend the Met Office!!
Fascinating to look at though!!