I think boas are somewhat like people.. cute and pretty as babies, more overall beautiful as they mature and then a different kind of beauty in later years.
Judging only by the intensity of the color most Boas get prettier with each shed through the late teen years, or about age 3 years in BCI.. After that they may darken or get more contrast or both. In addition many boas are metachroic, or change color, depending upon temperatures, hormonal cycles or perhaps mood.
Myself, I enjoy all the changes and have not been disappointed by any boa I've raised!
Good luck with those and welcome to the community of Boa-keepers.. I strongly believe the boa keepers are among the most passionate, forward-thinking and knowledgable of all the herp enthusiasts.
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Gus
A. Rentfro
RioBravoReptiles.com
www.riobravoreptiles.com
"Quality is not an accident. Perfectly healthy animals are a minimum requirement.. everything else is just salesmanship" gus