Fun model, kids love it! Negotiates the tracks much better than the fixed axle units found on most sets, and leaps better than fixed six axle units like "Thomas". Overall height is no different than others currently out there, so tunnel service is possible. Seems longer than a Thomas due to the axles being closer to a real locomotive configuration, but is not much longer in reality. I need to work on getting couplers (magnets) installed to make it more useful.
I messed up a picked up a 5mm bolt instead of a screw for the truck pivot pin, but worked ok.
Printed using COEX PLA. Engine is in what would now be their "Sparkle" pink. Trucks in a leftover run of White, and the wheels in their Aqua blue.
Used default settings in Slic3r, dimensions came out nice.