On the positive front, the machine is well made, has the facility to store 84 readings each for 2 users, and has PC connectivity - all excellent innovative features.
There are quite a few negatives, however. As a result of the inflexible 'one size fits all' comfort cuff, the whole package is twice as large as a regular bp monitor pack, so definitely not a model you would choose for portability or traveling.
I am also not impressed with the 'one-size fits all' cuff, which is very bulky and not easy to achieve a snug fit with if you have a slim arm, as mine is. In fact, I was initially consistently achieving very low systolic readings (up to 20mmHg below my usual readings), and eventually realised it was due to the cuff not fitting properly rather than to the machine itself being inaccurate. The main criticism is therefore relating to invention of these 'comfort' cuffs. If only Omron would offer the option of a variety of cuff sizes, but in fact this inflexible 'comfort' cuff seems to be the only size available to go with this model.
One final word of warning is that Omron seems to make a different cuff connection for each new model. So do not assume a cuff you happen to have for an old model would fit in this or any other new Omron models! I happen to have another Omron bp monitor which is only 1 year old, and this model's cuff does not fit the M10, or vice versa.