I'm a big fan of how my Citizen does it. City codes for every timezone spread around the face, pull the crown out and point it to whatever timezone you're after, pop the crown in and the hands move to the relevant time. Could be a bit faster at rotating though.
I thought that too.
Really digging this (with a black strap)
I'm a sucker for a hidden 2nd timezone hand... hands down the best way to GMT.