I have played both TSW and TS18 , And I can tell that there is no significant difference b/w both. the only thing TS18 is lagging in that the wheel physics that is absent in TS. Otherwise full marks to TS. TS has lot of positive over TSW. 1) You can free roam to whole world in TS.(2) Lot of third party scenarios available in workshop which makes it lot interesting.(4) Dynamic weather with location based climate change available here which is absent in TSW (3)If wheel physics and multiplaying is added it will be more superior.