I have now tested this Renner 3 days and am thrilled. At first he did indeed after about 5min nothing more but this was probably due to the first charge.
So from left to the lander (USB cable or via the remote control) and for one hour at rest. Then he went out again for about 1 / 2h. at Level 2. Maybe he was already full but I wanted to play it safe.
Conclusion: very small, very fast and great fun! Only 4 stars because the terrain barely mobile.
PS: I am pure fun riders and absolute beginners. Professionals should not be stopped in such price levels.