Ya, I agree with Grant. I bought a Thermor digital in/out hygrometer from the Building Block, and it died on me last week after only having it for less than a year. It fell off a few times, and the snake mashes it into the substrate quite a bit. Anyway, the display wont work now. I have a Radioshack model, and it has been subjected to the same loving, and is still working after almost 3 years. I think the key difference is its weatherproof construction.
Hope this helps.