Only one lily? * twitches *
It's bad enough trying to limit myself to the small amount of space I have, let alone a single lily! But if I had to choose, it would be the one given to me by my grandmother many years ago, which I think was a spotted orange dwarf Asiatic (not sure it's Orange Pixie, based on photos I've seen). Currently can't locate the lily, so sadly suspect I've lost it.
If sentimental reasons weren't a factor, I'm not quite sure which one I'd choose! Too many options...