Product review (5 stars): Seems pretty accurate to me
I was nervous about some of the reviews saying it had questionable accuracy.  The temperature both inside and outside the house seem like they're very accurate.  For humidity I don't really have anything to compare it to so I'm assuming it's accurate.  The humidity does seem to register higher when it's foggy or rainy, so I'm overall quite happy with it.

An unexpected feature I didn't realize it had was to register the highest and lowest temperature.  You do have to reset it to use the feature, it doesn't reset by itself every 24 hours or anything, but it's a convenient way to answer "how cold did it get last night?" or "how hot was it today?" as long as you remembered to reset it a day before.