Which statements of tacitus might you regard as reliable and which are more suspect why?

I would say that Tacitus was probably more reliable in his history of the Roman emperors because he was a Roman senator and would be very updated on the workings of the Roman Empire. On the other hand, his apparent denial of the existence of Jesus Christ would be suspect, given the weight of evidence to the contrary and though he was born only in 56 AD he. being of the Roman Empire would not likely be close to the followers of the teachings of Christ.