My Cosmic Flex Twin Micro just made it back to me from its journey. After they added a bit of extra material to the shell, it now fits like a glove. And the sound remains the same - exceptional for the price. Wow!
The BA1 is good, and I can definitely recommend it for those on a budget. But I think the BA2 or twin or whatever we call it is the better value per dollar as it really does sound phenomenal. If I move up to one of my flagship CIEMs I hear improvement in various areas but nothing that makes the Twin sound terrible in comparison. It really is an impressive achievement for a sub-$200 IEM, much less a custom molded sub-$200 IEM.