My daughter had another doll with similar silky hair, and it quickly got nasty and ratty, because she would carry the doll around my one arm, dragging it on the floor, etc. So I wouldn't get a proper AG doll for a preschooler.
She does have a bitty baby doll, which she loves. The clothes are very good quality, and can withstand manhandling by a small child. And the doll itself is half the price of the bigger ones, which helped my rationalization a little.