Graphics beautiful, yet needs a fas PC and graphics card. No surprise.
The game does not really know whom it is aiming at: on one hand a rather arcade-like driving experience (engines too strong, some built-in cruise control, trains don't feel heavy) on the other deeply simulated engine startup sequences and DPU configurations that won't please the "arcade gamer". Up to forced hardcore walking along the entire train (more than a mile there and back) with no shortcut.
Terrible sound, engine noise turns into white noise after some time - like in TS2017.
I pre-ordered it, because I obviously had to. First verdict after two hours game-play: much potential -- yet not really finished. But everyone knew that beforehand. If you buy it now you buy something like a late beta or so. It runs stable and without any glaring graphics or other problems. But as you already know there is NO route editor for now and also NO scenario editor and NO steam workshop. You have to do with what came with the game. Keymapping is very similar to TS2017, although some new keys for new features have been added.
My PC's specs are at the required minimum (i5 3,2GHz, Radeon 280X, 8GB RAM) and the game runs OK-ish once I switched the graphics settings from "high" to "medium". Although then it looks a bit like the now "old" TS2017. Let's say on "medium" it runs like a detail-heavy route on TS2017 - like The Aurora Racetrack for instance. It does not really stutter but you won't get much FPS. I'd say between 25 and 30 without having it actually measured.
You can now walk around the engines and the train, can refill the tank by attaching the fuel hose and you control the turntable from within the control booth. Nice features. In one scenario I had to walk from one end of the train to the other and with the train more than a mile long that took some time. I couldn't find a (keyboard) shortcut to just jump to the other end and that was annoying. After all it's a Train simulator, not a hiking sim.
Right now I've only really driven one of the three (?) different engines the game comes with (GP 38-2, AC4400-CW, SD 40-2) and I cannot really say right now how realistic it feels and whether the physics and sounds are better than those of TS2017 which were totally botched (I edited out a totally justified four-letter word - just to stop some people from crying. You're welcome.).
Will update this post once more details come to light.
Update 2016.03.16 23:45:
The SD40-2 comes equipped with some kind of cruise control: notch1 for instance won't accelerate beyond 10mph, the amps just go to zero. Same with other notches: they all seem to have a max speed beyond that the amps go down. Don't know whether the SD40 actually comes with this feature.
Sound seems as bad as it was in the old TS2017: after a while the SD40 sounds like an enormous hair dryer. Gone is the distinct metallic engine noise and everything seems to be only fan noise or white noise or something.
At least the heater works. Was afraid of being cold ...
Update 2016.03.17 15:25:
Same problems in the AC4400-CW: "cruise control" and sound that turns into some kind of white noise. Also the engines appear to be way too strong. It all feels like a train sim in arcade mode. Disappointed. At least the dynamic brake works better than in the SD40.
Update 2016.03.17 16:45:
Already mentioned by someone else: one save slot for the entire game (not one per scenario, like in TS2017). Ridiculous.
Nice feature: Simulation depth for starting and configuring engines turnsout to be much deeper as before: you can (and have to?) set up engines for DPU service, start up diesels and stuff.
What I really want to know but have to wait for: how intelligent is the new AI? Is is as bugged and stupid as the old one? Or maybe clever and fun to work with. We'll see.