Compared to other two I have, the difference in measurement stability is light years away. In any case, the feeling you get from the measurements is that you are dealing with a professional oximeter.

The best oximeter I have ever had so far. It comes packaged with a long string so you can wear it around your neck and not lose it. I work in a hospital, I have had this specific oximeter for 9 months, and so far it has never failed to measure oxygen saturation and pulse even in the most difficult patients. Obviously, I would not recommend it for common use. But if you are a healthcare professional or if you need it for home use in cases where a family member has a respiratory problem and common oximeters are unreliable, this specific oximeter is definitely worth its money.

Overpriced product. It shows the same results as other branded oximeters that cost about 1/6 of its price (medisana PM100, Beurer PO 35)

fast counting even in poor peripheral circulation, cold fingers or cardiac arrhythmia. The measurements are equivalent to those of the 2,500€ monitor

Excellent for professional use, fast and accurate. For amateur use, only if an elderly person has arteriosclerosis, then cheap ones are difficult to show

As a patient with spinal muscular atrophy, I have bought the cheap ones with flashy screens and they are not trustworthy. If you really need a pulse oximeter, buy a good one. If you need one for cross fit or something similar, a €25 one is fine.

Clearly an overpriced product due to the current situation. Small, cute, doesn't seem to be a sturdy construction worth so much money. However, I'm not an expert, so I can't say anything other than my personal opinion.
Update 2023: I have had it for a long time and it has never lost its measurement, while its measurements seem to be extremely reliable. In the end, it probably is worth its money!

I have tried three products ranging from 45-55 euros. They were unreliable and the measurements were approximate. This specific product, both in oxygen measurements and pulse readings, matches the measurements of oxygen measurements taken with blood gas analysis, and the pulse readings of an expensive professional sphygmomanometer. All of this based on my own experience with a loved one who needed to be hospitalized several times and there was a comparison.

The best portable oximeter!
By far the best! I use it very often as a professional, I have had it for 10 years with daily use, it hasn't had any issues.

I don't know if it's worth spending so much money on such a product.
I believe that with much less money, it will do the job just as well.
I don't want to discourage anyone from buying this specific product,
but this is my opinion which is not based on measurements or comparison with
any other similar product. I just can't swallow it!!!
Unless the saying "expensive perfumes come in small bottles" applies here too.