I got the large one (70 or 80lt).
Positives: it has a good sensor and especially in the first year it worked effortlessly with only one battery change, very close to the end of the year.
2. aesthetically beautiful
3. it is very large and fits a lot, which is also a negative.
Negatives:
1. the biggest negative is that the bin is made from second-rate metal. UNJUSTIFIABLE for such a premium price to have such thin, weak, simple metal (not stainless steel). It dents immediately. Twice it arrived with small dents. Yes, I asked for a replacement one time. It was very crumpled.
2. The metal is like from Lidl. Inside it is not painted!! After 1 year it started to rust and leave little bits around the floor that make a mess! Mainly for this reason, its price is extremely expensive for such poor quality metal.
3. At the very bottom it is perforated. If the bag leaks, which is more likely because it is large, it will make a mess everywhere. The base at the bottom is perforated on the sides and is not stable. Yet another point of poor construction.
4. From 60 centimeters and above, when you try to remove a full bag, it does not come out easily. If you are a woman, it is very heavy and even if you are very strong it sticks to the sides and pulls the bin upwards. The bag tears and punctures and you have additional accidents. I do not recommend the large ones. They are impractical. I regretted it. 50, at most 60, and change it more frequently.
5. After 2 years it does not open fully upwards, only half the lid. I took it apart to put WD40 and even the sensor and the system are of low quality.

I do not recommend buying it, unless the price drops by at least 50-100 euros.