I have the pH580. About 2 weeks now. I use it mainly to track my steps, Blood pressure and Blood glucose. When I initially bought it , it was accurate with my Blood glucose ( I use a at home device to manually check/compare my value). But recently it is not accurate with my blood glucose. Not sure why. I had it set to continuously monitor, which I thought was correct but showing my value higher than my at home testing is showing. Change occurred after I came back from my Jamaica vacation. Also my sleep monitoring was not correct on the hours as well. I was going to purchase one for my husband's bday, but may not do so since it is not working properly.