Product review (1 stars): Not accurate at all!
This AcuRite product is not AccuRate (pun intended) and the company support is non- existent.

I went through 2 of these units in the span of 2 months.  The first unit would show an outdoor reading of 91-98% RH, even though true RH was in the 35-45% range.  After bringing the remote sensor inside and placing it next to the base unit and allowing it to adjust for a day, it would register a difference of more than 10% to the base unit's RH.  I felt positive it wasn't anything I had done wrong upon setup: new batteries (lithium's for the remote sensor), placed in a protected location away from the ground and out of the sun, well within the stated working range.

That unit was returned and replaced with a second one.  Same problems with the added excitement of watching the outdoor RH reading vary wildly in a 24 hour time span.  Seriously, anywhere from 61% to 98%.  Really?  In a Wisconsin winter with the local stations showing a consistent level of 35-40% over a few days?

While the temperature readings were accurate - within 2 degrees both indoors and outdoors, this unit does not perform accurately at all in reporting humidity levels.  The layout of the readout is also not intuitive.  The plastic trim separates the outdoor temperature from the outdoor humidity number - foolish.  No response from customer service after two attempts, terrible.  The second unit was sent back too.

In my opinion this model is garbage at any price and I would recommend something else (I'm still looking myself).

UPDATE 2/10/2013: I attempted to post this review on the AcuRite website. They only display favorable reviews. No surprise there!  I recommend spending your hard earned money elsewhere!