Its working on GB stock and on ICS stock.
Just to confirm before i take the plunge - you have to either be running a complete stock version of GB or ICS and you can't do this if you're running a custom ROM (like Cyda's Stock+ ROM)?
And again, once you've done this sim unlock, flashing other ROM's won't remove it? Or (as you mentioned in the other thread), is it a case of doing a 5irom IMEI backup once you've done the unlock and then restoring that IMEI backup after you've installed different ROM's?
Certainly be interesting to hear from others if they've done this!