In one of those interesting coincidences Åsa writes about the issue of repatriation, returning items from museums to the countries, regions or peoples they come from, while PZ writes about his mixed feelings about Lucy going on tour in the USA. Both touch on the matter that unique objects by definition only come in a single copy which is fragile and can only be in one place at a time, yet at the same time we are for seemingly less than rational reasons fascinated by the Real Thing and will not be at all as impressed with a replica, be it ever so faithful to the original.
From my personal perspective, I associate to the still ongoing debate about whether one should fly warbirds. The arguments are mainly along the two lines that warbirds are too rare and valuable to subject to the risk of smashing them up versus how aeroplanes belong in the air and how they attract a greater audience than static aircraft, thus bringing in more resources for restoration and preservation. And here is of course an important point that the issue of what is an “original” is greatly blurred for both flying and static museum aircraft. In very few cases is a museum aircraft stored in the shape it was when it was active, and in to an even lesser extent is this true for flying aircraft.
While there are veritable “Frankenstein's aircraft” composed of parts from many individuals (though note that many, in particular military, aircraft are quite heavily patched up with parts from other, cannibalised, aircraft during their active life) many are an identifiable individual with a known history, but then they are restored—repaired, refurbished, repainted. (And of course, painting has to be done to prevent corrosion and other degradation.) Only in later times has there been a concern with doing this restoration in such a manner that the final results correspond to what the aircraft would have looked like “in life” and now it often requires painstaking work to figure out what has been hidden underneath layers of locally procured paints, applied in some, sometimes completely imaginary, interpretation of what it originally might have looked like. (If you have seen the painting instructions for the original Revell Fw 190 model from 1963 and their complete lack of relation to reality, you'll know what I mean.)
Quite often a particular aircraft is painted to “represent” another, more famous individual, sometimes with no consideration to the actual subtype. (It is as if Bockstensmannen was displayed in heavy makeup to be lifelike, dressed up as Gustav Eriksson (Vasa), as a tribute to the latter.) Too often is a Hispano Buchón presented as a Bf 109, in fake German markings, which I think belittles the certainly worthy service history of the Buchón. (And makes people believe the 109 had that godawful chin!).
So show some respect for the aircraft and show them as they looked during some part of their own career.