I couldn't find the meaning of this platform name: D probably stands for Dirt, but no idea for the N (New?). Anyway, this is a recent platform released in 2010 that only counts one “general public” kit because the development is made by the Team TRF.
58477 Zahhak (2010)
42167 TRF201 (2010)
42253 TRF201 XR Chassis Kit (2013)
42277 TRF201XM Chassis Kit (2014)
TRF211X chassis (environ 1991)
42288 TRF211XM Chassis Kit (2015)
The story of this platform, at the moment still limited to one unique chassis, was brought to life by the Team TRF who designed the TRF201, an all new race-oriented 2WD buggy. In fact, this buggy won the European Championship in april 2010, a few months before the Zahhak kit was released (september). By the way, Zahhak was a mythical character in the antique Persia whose name means “[he who has] 10,000 horses” (see the article on Wikipedia).
This buggy is very reliable and performs extremely well: to compete with the best modern products, it naturally requires several hop-ups to improve its characteristics, or better, you can directly go for the TRF201 version. Nonetheless, out of the box, the Zahhak easily outperforms any entry-mid level chassis such as a fully hopped-up DT-02 (for example, the DT-02MS version).
As for the TRF201, it is one of the very best chassis currently available on the market in the 2WD buggy category, making it pretty popular among club racers: in particular, it won the 2010 and 2012 European Championship and finished 2nd at the 2013 World Championship. As for its transmission architecture, experts can't miss similarities with the Associated B4, the model that dominates about all World Champion Titles since 2004.
The TRF201 received 3 major updates: first, the XR version, providing a longer wheelbase (by 11mm) and a narrower and rearranged bathtub in order to be compatible with more modern battery pack shapes. The second evolution called XM gave the ability to mount the motor mid-ship, improving the chassis performance on high-grip tracks. This evolution is widely spreading in the 2WD race industry and about everyone now offer this mid-ship architecture on race chassis: in fact, both due to improvements in the tire industry and carpet-covered off-road tracks becoming more and more frequent, the architecture of buggies now tend to mimic the Touring cars architecture. On carpet, there is so much grip that there is a greater advantage to recenter masses than to keep the conventional rear-mounted motor that was mostly made to add weight on the rear wheel in order to improve grip. Of course, you didn't miss “off-road carpet”: they call it modern RC
In 2015, Tamiya released the third TRF201 evolution, the TRF211XM: actually, it is based upon a TRF201XM featuring an all new bathtub made from a totally new composite material that is both lighter and stiffer. What's funny is the name of this new evolution: actually, TRF211X was the name of the prototype that gave birth to the Dyna Storm back in 1992. Of course, the name of the new chassis is not identical, but the allusion brings back memories.
Conclusion on the DN platform
In fact, the DN platform only exists to offer a “general public” version of the TRF201 chassis: so few models and evolutions are to be expected on the kits side because the design process is done by the TRF Team. Just like with the TA platform and the TRF41x series, only major evolutions will be transferred into kits versions.
Just like the DB platform we reviewed earlier, the DN platform proves Tamiya's firm will to enter the world elite scene in international races. From the beginning of the 2000's, Tamiya focused their racing efforts on the Touring category, up to establish their world supremacy, leading to very positive consequences over their brand image and sales in a major category of the market. Since 2010, in addition to their continuing efforts in Touring, Tamiya applied the same strategy in the buggy category, with the DB / TRF501-502 in 4WD and DN / TRF201 in 2WD.