>>1470533Its literally used in professional training, so it's taylored to model the german signalling system in full detail. For the dev the amateur market is more of an afterthought, but there is a reasonably big and dedicated fan community. Additionally, things in the zusi world aren't happening very fast. The green routes are the finished ones, and the game has been out for about four years now. Last time I checked Zusi didn't support switching operations at all, but that might have been adressed by now.
Make of that what you will. Its probably one of the most hardcore sims out there, but it's a bastion of german train autism if there ever was one. I'm not even sure that it comes with an english localisation.