Hmm, I think I would feel far too guilty if I sold or swapped any of my snakes because I wouldn't know where they would end up in the future. I wouldn't want them to be badly treated and I kind of feel that by buying them I have a responsibility to care for them as long as possible.
I do have corns at the moment and they aren't exactly my passion...there are some snake species that I would far prefer to own but if it came down to it I still wouldn't pass them on. I don't think its fair to say they are boring. I think that what people say they are boring all they really mean is that they are "common" and therefore not seen as "interesting" or "exciting" to own but I think thats a little harsh...why should it matter if heaps of other people own them? My personal reason for not enjoying them as much is that I like my chunky snakes. I prefer big chunky boas

...and no, thats not a penis size issue

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The only reason I could s ee myself selling up would be if I had huge financial problems (not enough money to feed myself let alone the snakes) or if it got to the point where I could no longer care for them through illness.