More efficient than battery models, but at a penalty price (almost as much as a sled vacuum cleaner) We reached the limit of this concept which normally means an extra vacuum. Here it seems that the goal is to catch up with the performance of a sled vacuum cleaner but that is not what is asked. The main point is maneuverability, ease of use. In this register (which is valid for models of this type), I find this vacuum rather unwieldy and too heavy (almost 4 kg). With this weight in his hand is made of the gym certainly, but it is difficult to hold more than 15 minutes, so it is useless to seek a super long battery life. Then the head is too large to fit in all the nooks and hard between the legs of tables and chairs. The handle is also too high (hard to take at arms). It takes time to really get used to its size (but I'm getting there slowly). Certainly, this model brings some significant advantages with its long battery life, given to 55 min and 30 min minimum speed in top speed, I tested and holds up well stack 30 min maximum speed and without any loss of suction (abrupt) -> very good point. The total load is given 6 hours which is long after tests it takes about 4:30 -> good point. It has a handy charge indicator (3 LED) and lack of other models, however on mine broke after 3 days after the end of charging it blinks continuously instead to stop and 2/3 displays a level when the battery is full (tested OK). This has no influence on the operation but at this price, it freaks still a little balls and it annoys me to repair it (I myself will solve probably before the end of warranty).
The life of lithium batteries is probably better as its investment so we can think up over time (to see). The brush is equipped with illuminating LEDs that can think gadget but in fact it is a super convenient idea that should be re-operated on other models. Aspiration is very good (this is evident by emptying), access to the dump is fast and without difficulty. The filter is washable (comes with one spare filter). Last positive, it stands alone (fortunately saw his weight) so fits easily into a corner (near a socket!)
In short, despite good performance and a lot of good practice ideas, I'm not 100% convinced.
Update after a few weeks of use: My model was changed and I no longer load failure. Also I got used to its size and weight and feeling better (I always find a little big head and struggling to swallow the larger crumbs). I actually really appreciate its high suction power and which is continuous (without loss of suction during operation) over a long period. Also I am more positive than at the beginning, in fact it's not bad.
