next please!
There are actually several unsolved next's in this thread, and I believe you may be in the happy situation to kill up to three of them with a single stone. Please read further.
nikos wrote:x2 cannot know if a label exists or if it is pre/post-pended, and brackets are legal label characters, how do i tell if there is a drive letter in the label to remove?!
That's the point. As there shouldn't even exist a letter in the label in the first place. I don't know how x2 queries a drives label, but in case it receives/generates some mash-up like "PrivateStuff (D:)", it does it the wrong way. I'm dead sure there's a proper way to ask for and receive nothing but the label.
This very pure label would solve both the drive menu issue, and more important, the "dirty" default value when a drive becomes renamed in-place.
Now, I wonder if this couldn't be also the reason why the new name requires a manual refresh. Did you notice the fact that folders are renamed without issues AND get a proper refresh treatment, while drives have to deal with the interfering letter, and don't get refreshed? Coincidence...?

Maybe. But doesn't it appear like a case of failing assignment? It sounds logical to me that a drive won't refresh in case it's incorrectly addressed. Something like, "Hey, Label (D:), come forward!!" But nothing happens, as "Label" did not listen, since he wasn't mentioned.
This would also explain why the auto-refresh works in windows explorer. No interfering drive letter there, and voilà...