I look at the amount of tipping and whether the scales are two-tone or monotone. I also look at the tails since I heard that with rosy boas dark colors show up fist in the tail.

Take that with a grain of salt though because to tell the truth I haven't bought a baby grayband in quite a while. Nowadays I pretty much have what I have and if I hold anything back I usually tend not to care much whether it darkens or lightens. I do pay a little bit of attention to color but mostly I'm trying to keep the pattern of the adults and not let my locality stock morph into something completely different than the originals. To that end a broad spectrum of colors usually works but I usually don't want to be producing 7 banded Blair's or mega triple alternate alternas unless that's what the wild caughts looked like. I do have some extreme stuff but it's not my main focus.
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