The robot is fine but less intelligent than X600, the path is more random, it was trapped three times in my apartment that was handled by X600 without any problem. First time on small step on top of stairs (fortunately didn’t fall down), then in narrow blind alley and then stuck under exactly 7 cm high area under the wardrobe. So I would definitively recommend X600. X520 has only three advantages. 1. Battery is twice bigger and it handles 80 m2 like piece of cake (X600 only on lowest suction). 2. It has remote that could control even the suction level and spot clening without need of smartphone. 3. Bigger suction (no big deal). My recommendation - buy X600, exchange the battery (hope the 5200 mAh will be selled separately soon) and buy the X500 remote for grandma separately. But even X520 will do the work.
The product do not Map apartment and don't save map. Have a button to clean single room. The app works perfectly. The customer care was wonderful, high level. I change for X600 Neatsvor