The SS4's have been a very long waited electric locomotive for those following modern day Chinese railways. These are very elegant locomotives, and Bachmann have done an excellent job in recreating them.
These are probably the most highly detailed models bachmann have released. Everything is super small, and delicate looking, but without the fragility of Haidar's locomotives. The paint work is generally very good as we've come to expect, however I noted on my unit that one of the headlight rings looks like it received only one coat of very thin paint where as on the other unit, its much, much fuller and definitive. Some of the lining is a little fuzzy also, but not overly noticeable. The lettering is razor sharp, and the road number specific detailing is very impressive. The dark blue variant has six porthole windows per side per unit rather than the five, however I see this as more of a compromise to save tooling costs, rather than an oversight. I would much rather have this color scheme in the line up rather than not! There is a bag of small parts which need installing - mainly bogie parts, antennas, GPS equipment, etc. Many of these are atom sized, and will require a lot of patience and concentration to successfully apply.
The SS4's are pretty nicely weighted. If these were single units, then it would probably be a different story. Both units are powered and connected via a drawbar with a locking hook. I'm not sure about the strength of the drawbar (and God help me if it breaks as its a very complicated precision part), only time will tell. The operation is flawless, with a similar system to Bachmann's passenger cars to ensure that both units sit almost touching each other around curves of just about any radius. They both operate (and should be operated as a double unit according to the prototype police), however the A unit can be run seperatly (the B unit cannot run with out the A). Thankfully both units are motorised - a huge relief, after the underpowered DF11G's. If there was one thing regarding the performance of the locomotives, it would have to be the speed, in which all my units run very slow - approximately 60kph running light engine and decreases depending on the length of the train.
While I've been a bit worried about some of the trends coming from Bachmann China recently, there are no such worries with these models. The mechanics are beautifully engineered, everything fits and performs exceptionally well. The pantograph design is no longer a clip in job (that after activating a few times would cause paint loss to the pantographs), there is instead a horizontally placed hook that the pantograph slides onto. The spoked wheels are made of steel, like the ND2 diesels which translates as better adhesion, longevity and better looks - especially if you're machining down those flanges (old habits die hard!).
Electricity is moved around the engine via a PC board and wires. They can be operated from wheels or pantographs/wheels via a selector switch on the PC board. The lighting is directional.
There is enough room inside the shell to accept most HO scale sized decoders. As per standard Bachmann practice, they have an 8 pin socket to accept any NMRA 8 pin decoder. There are also speaker holes to accomodate a sound card.
I've not yet converted my couplers, but they will accept long shank (#56/156) Kadee couplers and most likely standard #58/158's. Installation looks to be very simple - just unscrew the coupler plate, and replace. As a side note, the Bachmann EZ mate knuckles on this version appear to be a new design - although the same basic principle and materials from the previous design/s. The major notable difference is the coupler head size, which look quite a bit better, however I still prefer and trust metal knuckles, so these will be retrofitted in the near future.
These are the highest quality locomotives to have been released by Bachmann China, a super cool looking engine with incredible details and performance characteristics. These will not disappoint.