Task: Sentiment Analysis
Input (English): Review: Seems to work as advertised. I opted for the non-battery back up, as my heating system has electric blower, so if power goes, heating system does not opearate. Battery/non-battery an individual judgment.Pros: "ready light" is not so bright as to be disturbing at night, if it is a visible location, as mine is; simple plug in operation; you can test alarm manually.Cons: its a bit larger than it looks in the pictures, so depending on where you mount it, might be unappealing to actually see the unit installed in a highly visible wall outlet. Instructions indicate not to mount behind curtains, etc. as air flow might be restricted. However, I could not find a "micro" unit.Observations: Obviously no safe method to test if the unit actually detects CO.Suggestion: put a pass-through female outlet in the unit, as it uses one plug in the typical wall outlet, and this feature would be helpful in a older home with fewer wall outlets. 
 Polarity: Negative
Output (English): False