I don't own one, but rosies seem like great beginner snakes! I also have a baby ball, and I haven't really had problems with it. He refused his first feeding, but took the second, and is pretty tolerant of being handled.
I think that, even though they are really finnicky eaters, if you are well-read and are prepared for them to stop eating for a few months at a time, then you should be fine. The biggest reason I've found that people say the feeding difficulties make them bad beginner snakes is that new snake owners freak out when the snake doesn't eat and force feed it before it is urgent, causing undue stress for the snake.
I think you should be fine with whatever you choose, though, as long as you do your research, and shop around. (I think it's also a good idea to find a store that carries the full-grown adult snake of the breed that you want, so you can get a sense for it's size)
1.1 ball pythons (Huxley and Marla)
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* Mollie *