All fairly contentious, however:
Second-hand “my buddy says” stories carry little weight. Having said that, my buddy has sampled kei apples around Southern California, and he liked the fruit from the Exotica “mother” plants enough that he purchased cuttings.
As always, I’m sure, opinions may vary.
On kei apples generally: many are tart, but even sweeter ones have unusual flavor notes in the background that may not be pleasing to all. I’ve heard the flavor described as “weird apricot”, and, based on the ones that I’ve tasted, that seems pretty appropriate.
Julia Morton writes: “certain female trees have borne profusely in the absence of male pollinators”. Wikipedia claims (for whatever it is worth): “some female plants are parthenogenetic”. Self-pollination and parthenogenesis are separate phenomena, of course, but I wonder whether the distinction is of great importance for backyard orchardists. (Though parthenocarpic fruit should be seedless, a characteristic most will appreciate.)
I can only speculate whether such clones are extant in Southern California.
I do like them enough that I will probably eventually seek scionwood and topwork my seedling. (Which has proven to be amazingly robust, surviving insults that would have killed most other plants.)