I feel a lot like Abufletcher and Oldscaleguy. Some full-scale planes are simply art in motion, and while they may no longer exist, or are waaaaay too expensive to have the real one, or are too few to see very often, the pleasure of building one and flying it, and knowing that you yourself created it is hard to describe. I don't care to compete with others, I appreciate everyone's work, knowing the thought and effort that went into it, and I do the best I know how to make mine as much a miniature of the full-sized one that my skills will allow.
It is fun and very gratifying to fly one of these creations, but the maiden flight will make you gray before your time, and every flight is a study in focused insanity.