Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Intermittent Operation - Disappointed

The Heart Rate Monitor worked okay for about two months then became unreliable. The heart rate goes in and out of lock. Wetting the chest band helped in the beginning. The watch display started to fade after about one year. I was so disgusted with the reliability I decided to try replacing the watch battery myself....don't try it. I disposed of the watch/waste band in the trash.......no loss. The watch/chest band must be retured to a dealer for battery replacement. After reading HRM reviews I decided to buy the Timex Heart Rate Monitor at Costco for $39 (user replaceable batteries). All I need is a HRM that will show I have reached my target HR, I do not need all the bells and whistles, it's on the workout equipment.