Beton, I've found that the Tele, D.S. and real market faves can quite often be quite different.

As a matter of interest, I am under the impression that betting the Betfair fave on Betfair more or less breaks-even, yet from my somewhat scant research betting the Tele fave and also the D.S. fave shows a very small profit with Betfair - this was based on Betfair's last-traded price before S.P. was introduced.

Seeing that S.P. is just about identical to the last-traded price, I would not be surprised if backing the Tele and D.S. faves would still show a profit.