Here we have 4 Great models of SP 4449... and they race.

Daylightrains's 4449
JointedRail's 4449
mrtrain's 4449 (Don't get upset that it looks bad, its old. Like REALLY OLD!)
AND!!!
Bill Vu's "4449" (Its just a 611) :P

Ask in comments for the downloads, except Bill Vu's it was made illegally, and the download was taken down.