Well the best game for a person depends from his/her opinion.
For instance, for me, the best game i played (and still play) is for sure Hard Truck 2. Been playing it since 2003 and never got tired of it. About LFS, I can't say yet, because compared to HT2, I only played it for a few months...
And right now I'm waiting for over an year for the Hard Truck 2 sequel, Rig'n'Roll (the initial release date was January 1st 2007), and specially if there will really be released an European map and trucks add-on. (the official game map is in California, if I'm not mistaken, with american trucks).
Some info about the game, if you want to know:
http://www.rignroll.com/