Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Bottom line: it works

I was at my wit's end with my dog, Charlie, who liked to bark all night long. I tried other products, but then I read _Cesar's Way_ by Cesar Millan and bought this SpraySense Collar. The combination of behavioral changes (on my part) and the citronella bark collar has let us enjoy "Silent Nights" this holiday season. I'm sure the neighbors are happier, too.Bottom line: it works, and it's more humane than the other options.