Device works ok in first few weeks. After that, it keeps displaying internal error even with new battery. Reading only shows once every eight to ten attempts. This device will give you more frustration after using.

My Omron HEM-7211 shows the above but not every time. I have had my doctor check my blood pressure manually nothing wrong. It's a worry I do not need. Are these machines any good?!

As previous reviews have stated, the Omron monitor produces false results. The company will "recalibrate" and say it is OK but it still produces high readings not matched by Doctor's readings or wildly different readings on different arms or when taken a few minutes apart. The company will then maintain that their products are certified appropriately in Australia i.e. they don't care that their product is not fit for purpose.
Simple to use
Gives false results, usually higher.

i monitored my blood pressure for 6 weeks using OmronHEM7203. I went to the Doctor with the machine to discuss my results and he checked my blood pressure manually and using the surgery machines. His readings indicated my blood pressure was 140over 80. The Omron machine had consistently registered 160+ over 90+. I had 6 weeks of stress because of shonky technology.
Easy to use
Inaccurate

Handy but i'd recommend you have your BP checked manually or by a different machine every now and then especially if it gives you high readings not consistent with your symptoms.
Saves you a trip to the doctor or chemist every now and then
Has a tendency to inflate readings (give you a high and false reading)

As a nurse i dont believe this product is 100% effective. There are many contributing factors in obtaining a correct blood pressure, and when people arent taught how to do it properly they can get incorrect results which are very far from the correct result.
The convenience and security of knowing your blood pressure at home or at work, and to help you make secure decisions about your health in regards to blood pressure [if used correctly]
Inaccuracy. All too often i hear stories about peoples "normal" blood pressures but when admitted to hospital we find out they are using this equipment wrong and their blood pressure is not what they believe.

No need to go to the doctor for BP test, test your BP easily from home.
Affordable and it really works accurately with a fair price.
None so far!