Hope it doesn’t sound too stupid, But I haven’t really Upgraded to TSW4 I’m still playing 2 and have gotten back into it recently, so I noticed how TSW4’s Preservation content seems to be labeled as Compatible with 4, and it can sometimes come on sale so i’m wondering, if I purchase lets say Horseshoe Curve for TSW4 can I use it TSW2? So that way I can save some dough on a Sale.
If you buy old TSW2 Add-Ons, it doesn´t matter which "Version" you buy, unless there was an upgrade. You just can´t use newer Add-Ons in an older Version of TSW. If we now stick with the example of Horseshoe Curve, that means it doesn´t matter if you buy the TSW2 or TSW4 Version, since the route never got an Upgrade since TSW2.
Don't buy any preservation routes, current dtg policy is to upgrade them a little, and sell them parallely as new addons for full price again (lirr - lirr2.0).
The example of Horseshoe Curve isn't the best if you want to include TSW1 in the list, as it was released for TSW2, so it won't be available for this version. A route that was released for TSW1, like Great Western would be a better example. Not sure why it's different on Xbox, but on Steam for example, whether you buy an updated route for TSW4, like West Somerset, or Nahverkehr Dresden - Riesa, or updated for TSW3 Southeastern Highspeed, you'll also get the not updated versions of these routes for earlier editions of Train Sim World they were available for. In the case of Southeastern Highspeed however, you'll need to buy Class 465 loco DLC for the earlier edition of TSW, to also have it there (as it was merged with the route in the TSW3 update).
Some are actually really good. Brighton mainline is a preservation route and not buying it means you miss out on an awesome timetable. I don't have to list every good dlc because that would take way too long. You miss out on all german layers if you buy none of the german addons, so you just have an empty wasteland. So it would cause more bad than good for the player's experience