The build is not the most pieces of any set, nor is it the most complex, there were no real problems building it and it was pretty straightforward. The only problem I had was solved when it turns out you ned to have all motors connected to the second hub to test it. This is not in the instructions, but calling support they are aware of it and just plugging the motors in will allow you to test part two. The thing is pretty heavy, the bag of 100 "rocks" is a good touch and it is how the LEGO group is able to claim that this is the largest set by piece count. Those pieces are not in the model unlike the rough terrain crane so I don't count them. When playing with it, make sure to stow the steps and lock them in place, I did not do that originally and caught it in the carpet. The controls are well explained and the app works fine on my phone. The model is very smooth compared to most power functions sets as there are not a lot of complex gears in the boom. The boom and bucket are all moved by linear actuators. The new longer linear actuator is soing to be something to play with in the future. All in all, a nice build, fun and heavy. Lots of replay value. Most of the expense is in the electronics and the license I suspect. But it is really fun to play with.