I'm not convinced of that fav/over stuff for offshores. The money features on the Rx lines show a lot more bets on favorites and overs, but the money is usually 50/50.
In Vegas, there is no doubt the books hurt when favs and overs come in, because Vegas books don't let people bet anything anymore. They just want $20 drunken tourists.
Offshore, I think the money is evenly split. Just my opinion.
Maybe SIA and Bodog get more fav/over action but I don't think Pinnacle, Olympiuc and others do. I could be wrong of course.