For future readers of this thread with intent to pursue health data collection, here's another perspective. I use an Omron Evolv, which find really useful and durable. While it definitely costs quite a bit more, I think it's worth it for the iPhone integration and the excellent logging capabilities. If the intent is a legitimate health analysis, I can't imagine why anyone would want a low-priced solution. Now, I'm not typical. I have really crazy BP. Really crazy. Technically called "highly labile BP," it goes to extremes and tends to stay there, hard to trigger a reversal once it goes. Baroreceptor damage in the carotid artery from radiation therapy to the neck 15 years ago. I can pull 170/140 in front of someone wearing a white coat; I can print 80/40 after eating, drinking, exercising or 30 minutes settling in front of the TV. I can stand up on the train ride home and suddenly feel stoned beyond belief. A call to the CEO's office and I feel the pressure in my cheekbones. At least once a week, I fake that I'm tying my shoes just to get the blood back to my head. I see a good cardiologist every six months and I always scare the nurse out of her wits. The doc knows my story well, is quite a runner himself, and always likes to see a log of the week before our visit. "Keep up the riding," he says. Recommendations: log a lot of readings in lots of situations, for with everyone there's always variance (not like mine) and your doc will appreciate the broader dataset. Bring your device to a checkup appointment and see that it's fairly "close to calibrated" by letting the pro do one arm while the device does the other - match should be "close enough." And remember, especially around here, that Dr. Internet is not your friend. Find the right doctor for you.