I have one of the early runs and one of the new. The early run is a POS. It is noisy, grindy, wobbles, and is generally unpleasant to run. The new one runs much smoother. Mechanically they are very similar, including the same power truck, but the materials are different and the newer version runs much better. Be sure to check the screws holding the power truck halves together. When new they were too tight and it ran very stiff. About a quarter turn looser on all the screws made a night and day difference in how the new one ran.