"Awesome! <noreply@domain.com>" from header not showing properly

I have a project that uses MailChimp STS to send all system emails. Each email is modified using hook_mail_alter() and the from/reply-to is changed:

"Awesome! <noreply@domain.com>"

However, when I receive the email in my inbox (on any client) the from address shows up as just "noreply" instead of "Awesome!". Furthermore, I disabled the mailchimp module and tested using the standard mail system and when I received the emails the from address properly showed up as "Awesome!".

MailChimp was contacted about the matter and they had recommended asking the maintainer of the module.