Adult cat, or kitten?

[Benzadmiral]

As some of you may have gathered, I'm a cat person. Currently I have one, a tuxedo-cat part-Persian, age 9. I'd like to adopt one more (just one more! I promise I'll stop there!), mostly for me, of course, but also because it would give the incumbent, Miss Oreo, a companion and playmate.

I like big shaggy cats, and am fond of the Maine Coon and Siberian breeds. At a cat show this weekend, I spotted several possibilities.

1) A black altered male Maine Coon, only 9 months old (but already 14 not-fat pounds)
2) From the same breeder, an all-black female and a brown tabby-and-white female, both the same age as above
3) A 4-month-old brown female tabby and white Siberian kitten

All other things being equal (price, health of animal, distance from my home), which would be a better bet, a kitten or a near-adult?
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