Agree that growing out is rewarding, I enjoy the process, but it kind of depends what your tank needs or what you're looking to do.
At the other end, when buying very small fish you don't always know what you're getting and some may turn out to be culls. Had this happen with my first batch of Geo sveni, despite being from a reputable source. Got them at 3/4 inch, they turned out mostly malformed and weak-- and just to be clear, I know what I'm doing, I've spawned and raised thousands of fry. A few months ago I got another batch from another source, 3 inch juveniles. Perfect. Came in healthy and sound, no defects, growing well, color and fins coming right along.