We've really been spoilt for choice with road numbers, considering this type of locomotive was by no means considered one of the major classes in China.
The ND2 locomotives bring about a new standard from Bachmann China. While the models have ultra fine details, Bachmann have also made them robust enough to be handled. Each of the 10 road numbers released has unique details, mostly being in the horn arrangement and color and the pilot style/color. The wheels on these engines (although deep flanges, yet again) are particularly well done being of a spoked design, and the bogies themselves look terrific with the separate springs, although I'm not too fond with the material they've started using to cast them. It's very brittle stuff, so no bending! The windshield wipers are extremely fine, the best we've seen yet. The staff exchangers (those little parts included in the box) are now etched brass.
These are very heavy locomotives, despite their compact size. Wheel pickup comes from all 6 axles, and even with the shorter than usual wheel base, users should not experience any problems electrical pick-up problems. They are very smooth, although they give off a bit of a grumble that should disappear after an hour or two of running.
The lighting is directional, although unlike any of the other diesels from Bachmann China, these have no red colored rear lights! I believe this is a prototypical arrangement. The main headlight is the typical light blue LED, while the two side lights have a much yellower hue.
There is plenty of room inside the engine to add a decoder. As per typical Bachmann practice, there is an 8-pin plug for the decoder.
The ND2's have the easiest coupler exchange I've yet come across. They will accept Kadee #58 (scale) or #158 (scale w/whisker). The pilot simply screws off and the coupler drops out.
I pass on most of my locomotive/rolling stock wheels to my good friend Peter Oetterli who turns them down in his lathe. He has discovered that the wheels on these locomotives are made of stainless steel, as opposed to brass on all of Bachmann's other models. The benefits of stainless steel are it is stronger, has better adhesion to the rails and they can be polished up to give that almost chrome like finish as on the real railways. On the downside, it eats through the lathe tools a lot quicker than the brass ones!
Bachmann's highest quality diesel to date, hopefully many of the features will pass through to future models.