Review on 🔌 Enhance Your Marble Genius Experience with Marbles Accessory Add-On by Jeff Johnson

I purchased these extra balls along with the Marble Run Super Marble Genius Set and some extra accessories for my son's birthday. One of the extra kits (the booster kit) has some parts that are open in the middle with small guides on the sides (see attached photo). Balls of the right size glide "easily" over these tracks without any problems. We found that many of the 60 marbles in this set were not the right size for these lanes. The balls get caught or stuck between the two side rails and do not move. We have (so far) found at least 30 balls out of 60 that don't work (we shipped each ball individually to see which ones got stuck). I find it unacceptable for a company to sell these marbles claiming that they will work with their marble bridges and accessories when obviously not all will work.