From a employee perspective, I'm totally fine with contract-to-hire as long as they are not abusing it to only use it as a 90 day contract with the hopes of conversion. Outside of that, I think it's up to me as the interviewee to gauge if I'm a good fit for the requirements of the opportunity. If I feel I am, and I like to think I'm a good judge of that for the most part, then I know I will convert at the end of the trial period.

And hey, if it doesn't work out then it doesn't work out. On to the next opportunity.