CK19 1.3 inches TFT Color Screen Smart Bracelet IP67 Waterproof, Support Call Reminder /Heart Rate M worth to buy? Thanks for it if those of you who have purchased CK19 1.3 inches TFT Color Screen Smart Bracelet IP67 Waterproof, Support Call Reminder /Heart Rate M could share about what you think of the product. I would love any extra info, as it is quite pricey as $41.80 and I just want to know it is good before paying for it.