Thought I would share a bit on just where all the 10 hrs of build time comes from!
Models of this type are made from greeting card paper stock of different grades, to create "structure" you laminate multiple layers, I don't have the kit in my hands yet, but it would not surprise me if the flywheels and beam are 6 layers(or more). The cardstock model crowd are constantly searching for the ultimate glue, water base glues cause warp and curl, but can be used IF you dry sub assembly parts clamped...say between premium hard cover books and weighted down. The hard core guys have even gone to the extent of having a few small plates of thicker Glass plate to use as premium "dead flat" drying fixtures! Solvent base glues are prefured and thick super glue drys "Hard" and water proof, so adding much needed structure but can be more difficult to work with.
If you have a Large number of hardcover books And a large work area to have Many parts drying "in the press" you likely could cut build time in half or better!
These kits Can teach youth valuable craftmanship, woodworking and laminating skills....I might Also suggest that person's with skill sets similar to say Jan and Bruce for example may be better served just bringing a youth out into the shop and teach them valuable Metal working skills! (And problem solving skills in general)
I don't think it's quite fair to compare a paper cardstock model to our traditional steam models constructed from what I like to call semi-precious metals, things like Silver solder, brass, copper, bronze, Nickel and cast iron are high value materials and thankfully many of our small models require only a few lbs or sometimes only a few oz of these premium material.
Also there Are a few persons that are never more happy than when they are building "something". the final product is not as much of a "prize" as the relaxation time! I may like to argue that time building paper models IS higher quality than say watching tv or playing video games! But agree that shop time spent creating things of Lasting quality is "Greater" than Cardstock modeling. The beauty is everyone can enjoy there free time in the way that gives them pleasure!