I can only speak for myself, and being used to LFS I _may_ be slightly biased
When you download LFS, you download the entire game but only have access to demo content until you acquire a license, so yes, it all fits in there.
LFS
+easy to pick up online races
+easy ui
+plenty of (fun) cars
+loads of track configs
+uber-cool community (
)
+free updates
+S2 is not feature complete, you will see more added to the final S2 and all this content is already paid for when you buy a license for S2 'Alpha'
+auto-x editor
+track (grip), drift, mess about, rally
+awesome physics
+good ffb
+stable online mp
+
-sounds aren't the best
-graphics are a bit basic
NKP
+good physics
+1 yr of free updates
+ffb when driving over rumble strips
+gfx
+sounds
-less cars
-less tracks
-open wheeler single seaters only so far
-ffb otherwise
-flat boring track design
-gui
-multiplayer (i haven't tried because i don't own nkp, simpy what i perceive it as)
-1 yr of free updates (then what?!)
?community, dunno, am not involved
In short, LFS is just so much more accessible and fun out of the box while being much more broader in scope and not limiting itself to ultra-hardcore racing only, with ultra-hardcore drivers. LFS it is.
LFS