Cleans well, but is slow and uncoordinated

Cleaning power:
Is really very good. When the robot times caught a dusty place, he makes clean thoroughly.
With the brush forward, he transported the dirt neatly to the middle and suck it up.

Navigation / orientation in space:
My first test was an absolute standard case: A living room with table and chairs, charging station with docked Navibot is in the same room. Here we go with the "Auto" function, explored it and cleans the robot automatically.
-Navibot Starts and takes about half a meter away from the charging station
-Navibot Turns and drives around its own charging station
-Navibot Turns again and moves a bit uncoordinated through the space, collides with cabinets and table legs
-Navibot Drives sometime between the chair and table legs and then acts quite helpless because he can no longer find the exit
-I "liberate" it manually by asking two chairs to the side, then he finds the exit
-It Continues with a cheerful Kolissionsfahrt through my living room.
What surprised me greatly: Some obstacles he realizes decelerates and scans ran itself. And some obstacles he ignored completely and goes head-on with full speed against (eg against its own charging station: -D).

Next Test in the kitchen without chairs and table legs, small room with about 15sqm. No obstructions in the room. All cabinets have at the bottom a bottom bar, so that the cleaning area is clearly demarcated. So he does not need to go under cabinets.
-Navibot No charging station will restart in the automatic mode, this time in space
-Mitte Of space is relatively well cleaned, every now and then he surprised at full speed against a wardrobe
-After He has drawn a large area, he apparently wants to clean the edges and corners. That works quite well in the beginning, he feels his way (this means that it runs on Kollission with the edge) at an edge along. There seems to please him well, because this edge he sucks about 20 minutes. He then goes to the next edge portion and makes there just continue.
-After The section is done, I turn it off.

Time saving:
-Not Yet, because the robot must be supervised, if he goes somewhere once tight.

Cleaning:
-Is Very simple, the hopper can easily be seen, open the blue door and just shake.

Accessories:
Very extensive:
Charging station
-2 Guards, with which you can lock area virtually. However, these devices need each 2 Mono cells (very thick) and who has already nowadays still in the house? Normal AA batteries would have done it.
Swirl -Ersatzbürste for both the suction and 2 replacement brushes the dirt toward the center
-Ersatzfilter
Remote control incl. Batteries
-Reinigungsbürste

Conclusion:
I am disappointed by the device. The main weaknesses are the constant Kollission with obstacles. Characterized scratches will arise on the robot and the cabinets in the long run.
That he umrempelt its own charging station when cleaning, is an absolute no-go.
The "little rascal" acts often totally helpless and uncoordinated and takes too long to clean a room. In my small kitchen with 15sqm I canceled after 45 minutes, although the room was totally free of obstacles.
I can only advise against the purchase unless you have large exactly rectangular rooms without furniture and obstacles (which would be pretty sad). For a gymnasium, the device would be well suited.