[werk_ag]

Hi Werk,
I haven't used SHT2x at all. Not sure if they (china) are using that name for HTU21 sensors also...

The HTU21 chip have the same pinout than the SHT2x (can use the same board), but is a different chip, which requires it's own reading method.
It is produced by Measurement Specialties, with Headquarters almost everywhere on the world.

"Based on a unique capacitive cell, digital humidity sensors from Measurement Specialties are specifically designed for high volume automotive, medical, printer and humidifier applications."

The specs sound good, but the very low price may also means something else, which by your experiences, may be a shorter longevity.

Here is a link to the manufacturer specs: http://www.meas-spec.com/product/humidity/HTU21D.aspx#