@natefreezy In my opinion it has more character.
The regular indigo looks like what a regular pair of jeans should look.
The indigo/black is “richer” ( can’t find the right word ) and versatile- it can be dressed up or dressed down when new; and as it starts fading, it looks with more character.
Don’t get me wrong, I have a pair of 21oz 555s in regular indigo and I love them.
The way I use them is, the indigos are my goto when going casual. The IB my goto when going “smart casual” to the office and whatnot (when they fade, they will become casual too).