K2 3D Color Screen Display Bluetooth Smart Watch, IP68 Waterproof, Support Pedometer / Blood Pressur worth to buy? Thanks for it if those of you who have purchased K2 3D Color Screen Display Bluetooth Smart Watch, IP68 Waterproof, Support Pedometer / Blood Pressur could share about what you think of the product. I would love any extra info, as it is quite pricey as $45.18 and I just want to know it is good before paying for it.