My 9 yr old lad has loved lego for years and this was his introduction to technical lego. It has gone down a storm with him pretty much completing the model on his own, with me only being their to guide him and act as an extra pair of hands for the tricky parts. In building the model my lad has started getting an idea about how engines work with pistons and how steering in a car works. All good stuff if you ask me.
We are now looking for more technical lego with 'Lego City' models being so last year!!!!