Hi Ice,
By purchasing the V2 basic set now includes the following-- taken from the Run 8 Studios web page;
Included Routes and Features
*UP-BNSF Mojave Sub
Includes Tehachapi Pass and the Palmdale cutoff betwen Mojave and Hiland
*Barstow-Yermo Yards
Includes working hump at Barstow with retarder brake squeal sounds.
*BNSF Needles Sub
*Includes a cool new shadow system (included in the latest update).
*Includes new environmental lighting and weather systems (clouds, thunderstorms, fog).
*Includes smart AI locomotive engineers that obey signal indications and track speeds.
*Includes an improved track and switch system (looks mobetta).
*Includes the ability to create a true train simulator world by being able to merge routes with new routes such as the BNSF Cajon Sub and the future BNSF Seligman Sub and BNSF Bakersfield Sub.
*Includes working defect detectors which produce actual random defects to fix.
*Includes accurate signal systems and dispatcher boards for routing player and AI train movements.
*Extensive help documentation.
*Version 2 is compatiable with version 1 content!
The V2 upgrade then affects the other sets like Cajon Sub, CSX A-Line, and iirc the Selkirk/Mohawk routes. They've made it easy to import V1 route sets into V2- just follow their instructions. Any extra packs of locomotives, and or rolling stock you may have already purchased in Version 1 are fully compatible and seem to be upgraded into V2 versions.
Is it worth the time and money to buy the upgrade? For me it was worth getting just with the introduction of functional AI since I'm not using the MP feature. The V2 AI gives the impression that you aren't alone and works well in it's present state-- what it isn't is an activity editor like in MSTS, or scenario editor for TS20XX. The AI system allows for proper consists to spawn in a variety of yards, at a variety of times. The AI crew (engineer and conductor) will then operate the train as per operational rules (i.e., track speed limits), signal indications set by RTC (you) on the dispatch board(s). Depending on the number of trains you use/spawn being the dispatcher/RTC can be a sim unto itself. I know of a few players who let the AI run the mainlines while they operate the yards and or locals.
The graphics upgrades are welcome, including the UI upgrades, but Run 8 is certainly not eye-candy like Trainsim World (DTG) or Trainsimulator 20XX (DTG).
I enjoy this sim for its simulation of rail ops as well as the driving aspects (cold dark start anyone?) and detailed physics. Despite the lack of photoreal graphics I find it very immersive (at least until the missus yanks my ear). As with any sim YMMV