Confirmation hearings

I have little doubt that John Roberts is going to be the Chief Justice of the Supreme Court for a long, long time. Whether this is a good thing or a bad thing kinda depends on what you take away from these hearings. Roberts is presenting himself as someone who respects the rule of law, precedent, etc. etc. etc., like all good judges are supposed to. He refuses to answer questions on things that he might have to rule on later, he believes in the right of privacy, just like any other nominee would, regardless of political persuasion. My issue is that who's to tell if he's lying or not? Who can say with any certainty that Roberts doesn't actually and fervently believe the things he's saying today, but that he might change his mind 1, 5, 10, 20, 30, or 40 years from now and become a raging lunatic hell-bent on upending our skeletal welfare system, or eliminating equal opportunity under the Civil Rights or Voting Rights Acts?
This is the problem I have with lifetime appointments and our confirmation process. People change over time, and there's very little chance that once appointed, any judge will be taken off the bench, especially one with as high a visibility as the SC. A judge might be completely competent today, but become mentally unfit tomorrow, and only in extreme cases can we do anything about it. More to the point, though, I feel little comfort in the knowledge that Roberts might be saying the right things, for the most part, because I have absolutely no trust in the abilities of the person who appointed him. There are obviously many things about Roberts that we don't know (all easy cynicism aside, why else would the Administration refuse to obey the law and hand over the documents requested by the Senate?), and they won't come out through these hearings, either. We won't know who this guy is until he begins to rule on cases--surely no sane liberal/Democrat would have voted to confirm Thomas, for example, if they knew he would become Scalia's lapdog out on the right wing fringe, do you think?--and by then it's far too late to do anything about it. He doesn't have enough experience as a judge (oddly, that isn't an issue when appointing a Justice of the SC) for us to evaluate him on his rulings, and questions about his work as a lawyer can all be sidestepped by claims that everything he ever said or did was at the behest of his clients. Our ignorance of who John Roberts really is should be enough to disqualify him--there's no there there!--but unfortunately, the process works in quite the opposite fashion. Since there's nothing obvious to object to, he'll sail through. I'm as scared of him as I was Ashcroft, Ridge, Brown, and all of Smirky's other appointees, but I'll be living with this clown for decades, and that makes him potentially much more dangerous . . .