This is certainly a better model for how real-life trains work but at some cost in playability. Chris Lawson is, as I type, hard at work producing a version which should be ready shortly - watch for announcements in the usual places. It's not really a kit, in the sense that there is no need to laminate and cut out the components, though it's not really of commercial quality. 1831 covers more or less the same ground as 1830, that is, the north-eastern US, but on a somewhat larger map with much smaller hexes. Trains can carry freight, passengers, or both.
Companies can merge to make systems, and systems can lay up to seven track tiles per turn.
While it's true to say that you certainly get a lot of components for your money, the game is just too large to play at a single sitting. To cap it, there is also a rules problem whereby it's possible to double your investment in a company in one round without actually running any trains, and the game is heavily slanted towards running in the New York area and starting a company elsewhere almost certainly means you won't win. As an exercise in taking 18xx games beyond all natural limits it succeeds, but there doesn't appear to be a game in the box, which is a pity. When 18xx devotees gather together, the choice of game is now rather wide. My own collection includes nearly 20 different games, including the commercial ones.