Review on Experience The Thrill With ROKR Marble Explorer Wooden 3D Puzzle Roller Coaster Kit - 260PCS DIY Mechanical Model Educational Toy For All Ages! by Damian Lousteau

As in previous similar models from ROKR, the instructions are very clear and the parts are very precise. At the completion of this one, I had several small numbered pieces left; presumably ones that were felt to possibly break. Here are a few possible improvements:1. Page 12 - part D36 left end does not connect to part D29, at this point.but finally does on Step 16, page 14. Maybe a note to advise of this, would be helpful.2. Part Z on Step 44 does not fit in place unless I removed the left-side F22.3. Step 46 - It appears that G1x3 should be G1x4.4. As with previous ROKR kits, the strength of the wood is adequate, but the large gears seem to twist or warp, so they do not rotate in a completely vertical plane. This cause the meshing gears to slip, sometimes.