Yep, entirely agree, Adler. My top five would be (in no particular order) - and this is the entire collection as opposed to a particular site; bearing in mind the historic nature of the airframes contained within;
The RAF Museum, The Smithsonian, The Musee de L Air, the USAF Museum and the EAA Air Venture collection.
The RAF Museum, The Smithsonian, The Musee de L Air, the USAF Museum and the EAA Air Venture collection.