There are just a lot of things why I love LFS:
1. Best physics ever. (I spend many hours just playing LFS, watching replays, going around with Shift + U, watching the physics in slowdown, and I never get tired)
2. LFS World is just perfect, I'm using it as my Windows desktop right now
3. Best Graphics
4. There are a lot of tracks and cars, and we are getting more and more.
5. The development is amazing, looks like the devs work on LFS everytime, there is always a TEST patch coming on and every time I download it I get just amazed on how much things they've done to the game. And I always love to help, even if I get just a single bug report.
6. There are a lot of servers online with so much people to play it at anytime
7. The best Multiplayer mode I've ever seen! 32 people on a server, and no lag.
8. Skins are just perfect. You can edit them in just any image editor and do whatever you want! how could it be better!?
9. Incredible damage system, even on the car body. (just needs a bit more work but its still incredible and I can't complain on that)
10. The game with the highest FPS ever. A MX440 is a lot more than the necessary to play it on high settings (even though I have a 8600GT)
11. Easiest game to play: put it anywhere, click on LFS.exe and you are racing. No need to reinstall when you format windows, no need to reconfigure after reinstalling windows, the game still the same thing no matter what you do [changing directory, format windows, etc]
12. The people on the forums, on the servers, the devs, everybody I've seen are incredible, they are friendly, easy-going, they make you Welcome to the game and playing with them is worth it. I visit LFS website and forums everyday, though I don't speak so much
13. The game is cheap. Though here on brasil it costs R$100 (Reais), but this is the normal price to every PC game.
14. Configuring a steering wheel could never be easier: connect to the PC. open LFS. Turn it to one of the locks, then to the other lock, and you are ready to play properly.
15. and of course, a lot of other things but I have no time to mention them here