NORTH EDGE CITI 98 1.4inch Full-touch Screen Heart Rate Blood Pressure Oxygen Monitor BTV5.0 Smart W worth to buy? Thanks for it if those of you who have purchased NORTH EDGE CITI 98 1.4inch Full-touch Screen Heart Rate Blood Pressure Oxygen Monitor BTV5.0 Smart W could share about what you think of the product. I would love any extra info, as it is quite pricey as $53.75 and I just want to know it is good before paying for it.