CHIGU C7S Fitness Tracker 0.96 inch OLED Screen Smartband Bracelet, IP67 Waterproof, Support Sports worth to buy? Thanks for it if those of you who have purchased CHIGU C7S Fitness Tracker 0.96 inch OLED Screen Smartband Bracelet, IP67 Waterproof, Support Sports could share about what you think of the product. I would love any extra info, as it is quite pricey as $33.30 and I just want to know it is good before paying for it.