Instruct: Classify Amazon reviews into positive or negative sentiment
Query: GPS reception is very poor

I bought the watch a week before the Houston Marathon, primarily for the GPS functionality and the design. I tried the watch out the night before, and got a signal. However, I tried to get a signal during the marathon, on a clear sunny day with no obstructions and didn't once get a signal. Very frustrating. I've tried several runs subsequent to the marathon and never got another signal. I'm returning the watch.