It's a waste of time imo. I don't want to keep labelling my regs, and I don't see why I should have a dedicated reg to "Nx50". Having one (a few) for oxygen clean content, sure! Knowing which ones are clean vs the ones that aren't, sure!
You're not the only one doing it, quite a few people argue that it is much safer, I just don't feel like it's gonna save you (you is a general term, don't think I want you dead
![Winking :wink: :wink:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
). If you already didn't read the tank you took the reg from, why would you read what's on the reg? And if you had read the tank, then you are on the right reg (because it wouldn't breathe if it were the wrong tank).
I'm also not involved in dives with 12 gas switches and don't think I ever will, so that might have some influence.