This kit appears to be extremely well made and engineered. Considering the complexity of the kit, it is easy to build. Although there are a few minor difficulties, these are significantly less than other kits I have built, although most of those kits were several decades ago. The shaft hole for the cam disks is cut slightly off perpendicular, so that they are not perfectly perpendicular to the shaft, but that caused no functional problem. I experienced none of the problems described by other posters, although I got sloppy and broke one piece that was easily glued back together. My wife suggested that I start collecting these, which I may do!

The laser cut components are extremely precise, and fit quite well. Quite a bit of force is required to squeeze some of the parts together, so you will need strong fingers, but that is intentional to insure that the parts stay together without glue. The design is very elegant, and quite attractive when assembled. Flexure cuts allow interfering socket joints to assemble, but really hold together. For a couple of the last components assembled, I did use some wood glue, but very little. The sequence of assembly in the instructions could be improved, but overall it works. It is a challenge to assemble, partly due to some very small parts that are a bit difficult to handle. Make sure you are up to it, because it may get frustrating if you do not have at least some assembly skills. This would be very difficult or impossible for a child to assemble. The design is very educational, using a gear train, cams, a walking beam, indexer, and a toggling diverter. A wax lubricant is provided, with instructions on where to use it during assembly, and it is necessary for parts that slide against each other. Kids that play with this will almost certainly develop an intuitive understanding of mechanisms, which can prove very valuable later in life. If you want your child to develop an intuitive understanding of mechanisms, or if you just love cool devices, or both, this is excellent! A work of art and engineering.

I'm a software engineer. So this artfully designed engineering marvel was an easy choice for me. It took me and a friend around 5 hours to assemble. The step-by-step instructions are very good. There were just a few moments of confusion. It is almost entirely of wood, and nice quality wood at that. It doesn't use any glue, although you should have some wood glue handy in case you break something or feel like adding some strength.

Purchased this for my nephews birthday 14th birthday. He has always been a “lego kid” that likes to think outside of the box. According to my sister, he has spent hours building and rebuilding the designs. See a mechanical engineer in our family’s future!

This is interesting and fun to build and actually works when it is complete. Really nicely made kit.