Yeah their backs brown out. But their sides don't really. They look pretty darn sweet if you ask me.
I love pastels more than any other morph.
Idk why but i do.
Here's my guy who has kept his color very well I think.
He's a normal pastel I got from a local reptile shop.

Just a side shot to see his Browning.

Just look for the brightest young one you can find.
Most likely he'll keep his color better.

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