Instruct: Classify a given Amazon review into positive or negative sentiment.
Query: Great product

Based on other reviews I choose the RS100. I love it! I really enjoy using it in the water for my laps. That was a awesome surprise. I would recommend this product, but had troubles during my last half marathon and bike ride. I couldn't get it to read my heart rate and keep it for the duration of my workout. Disappointing to carry it without it working and not quite sure why, but next time I will make sure its working with no interference before heading to the start line.