Fixed that for you. If Valve got their hands on it, they'd switch to a crap engine (sorry, but Source was/is horrible), well, more crappy. Then they'd stick a $60 price tag on it, update it once a year, and change the support service to a lone basement-dweller named Todd who pastes generic answers in as ticket responses. Finally, when you've had enough, he'll tell you that 90-day refunds are "against our policy" which is illegal as all-git-out. As you can tell, I am not on good terms with Valve.