After careful and scientific consideration, I can now make the final observations:
Trump vs Bush I/II
What makes Trump outstanding is that he is able to express and defend an opinion. Yes, it is true that he might be expressing a contrary opinion the next day, and his defense might be incoherent and cause even more troubles for his point of view, but one has to start somewhere. Bush I/II never made it that far.
Trump vs McCain
A consistent behavior of Trump is the picking of fights with various people, even if it is a pointless one. In this, however, Trump shows himself to be principled by first making the recipient of his attack into an enemy, then attacking. Later he might de-enemy the person and all is well. With McCain, it is his friends who need to worry the most.
Trump vs Romney
My main recollection was that Romney was a conservative Christian before being nominated and a born again RINO afterwards. Who knows what he would have become had he been elected? There is only one Trump so you always know who it is you are voting for. OK, so we have to deal with this in a statistical sense with a very large standard deviation, but we are confident that the alternation between positions and their complex conjugates is a stochastic process which is temporally invariant, rather than being subject to discrete jumps and singularities.