I’ve had mine running since February and I love it. Im very satisfied and well worth the investment. I’m on a schedule testing ALK, CA daily, NO3 and PO4 every other day and Mag every couple days. I just have to switch out the 3 NO3 reagents and out in the 3 mag. It’s fairly easy to adjust the app for the new tests and it saves your data. As slewrock points out you do get some bad readings from time to time, but I’ve found that it’s almost always human error..reagents to low, waste full, need to change needles, RO res empty.. I do burn through reagents but you can buy refills instead of full kits.. but it’s doing a lot of testing. Much more than I was or would be doing manually. I’ve found results to be very consistent and I trust them.