The model runs very well. It is one of my personal favorites and the one that I go to if I need to test for any track problems. It has an ABC motor/gear unit and wiper current collection from the four driving wheels and the rear pair of bogie wheels. It has been very well built by a person who it is clear was a very accomplished model maker. The rear axle is allowed to move vertically in hornblocks and guides, the front driven axle is fixed. The loco negotiates 6 foot radius curves without derailment or shorting problems.