D10 1.54 inch Screen Display Bluetooth Smart Watch, Support Pedometer / Heart Rate Monitor / Sleep M worth to buy? Thanks for it if those of you who have purchased D10 1.54 inch Screen Display Bluetooth Smart Watch, Support Pedometer / Heart Rate Monitor / Sleep M could share about what you think of the product. I would love any extra info, as it is quite pricey as $57.99 and I just want to know it is good before paying for it.