My 11 year old daughter has built a few iterations of this robot and really enjoys it. The solar panel came broken (we improvised with a battery initially) but Unicorn replaced it hassle and cost free.
Spent some time building this with my daughter and she loves it. No problem building it, and customer service was excellent.
We have lots of sun here in Manitoba so my grandson had hours of fun with this toy. It was challenging , but he is smart and figured it out eventually. Kept him busy for days.