Point deduction, there are for the electronics. The remote control is not always reliable and skips. The receiver on the balls also do not always react, so it may happen that some balls tackle, while the others go out and vice versa. In addition, the batteries should last only a few hours.
Fortunately normal LEDs with 3V forward voltage are installed in the balls, so that they can be operated with series resistance easily to external voltage sources. We have now made the third winter with the balls as Christmas and are very satisfied. You have to tinker a bit and soldering, but the effort remains limited.