Prefer Fred Thompson...for a myriad of reasons.
But in the end, if the GOP flips the proverbial bird to us and serves us Rudy, he gets my vote as a vote against the Democratic Party candidate.
If it comes down to Giuliani vs. Clinton, et al, I'm not going to condemn anyone for voting for Giuliani, because at that point we've lost anyway. I do take issue with people claiming to be conservatives who have been pushing Giuliani for months and attacking other more conservative candidates.