Instruct: Classify the given Amazon review into positive or negative sentiment.
Query: average at best

I found the units to be hyper-sensitive at first and then in less than 30 days, 1 of the 2 units stopped functioning all together. Not worth the postage I would have to pay to return the unit for replacement. Lesson learned..."as seen on TV" is only seen functioning for :30 or less. With that as the standard - it worked.