Although useful for analyzing a problem of sleep apnea

Update after 1 month of use: I confirm that this is a good, useful device for understanding a pb of sleep apnea, and more features than I had seen in the beginning but in absence of instructions, we must grope a good time to discover the software.

The technology made enormous progress and it's amazing to find this type of device for such a low cost, this allows for very interesting investigations, with all the necessary time.
But still some points that could be easily improved:
- Instructions provided only in German (you have to look on the internet a manual in English, which could at least be in the PDF CD..et there is nothing in French ...) and not in terms of technology the device.
- Software provided only for Windows, for Mac very complicated, load emulation windows ...)
- Software provided no explanation and we must grope at first, note: you must go to "print" to access analysis with statistics saturation and heart rate
- Data transfer between device and sometimes random computer, you have to start ..
- Monitoring functions quite well done, with alarm threshold settings.
- Be careful to use only the supplied USB cable, there is a converter in it ... which is not clear ....