The VAST VAST majority of sexual related crimes are NOT taken to jury because of the stigma associated with those types of crimes. You will most likely NOT get a fair trial in a sexual related case. In a "hand on / aggravated" offense I would agree with you. You have nothing to lose. But in all other cases better to take the deal.
You could request a bench trial if you think the public at large would be biased. Unfortunately in the US this requires consent of the prosecutor. The Ghomeshi trial in Canada is an example of using a bench trial in this circumstance.
Yes you are unlikely to get a fail trial, but when you are facing a life sentence of being on the sexual offenders register if you plea I would still take the chance on a trial (I am of course assuming here that I am innocent).
