Of course you can easily see and feel the difference, but have to have it in your hands.
The asian movement allows the GMT-hand to set the GMT time smooth and easy with.
The swiss ETA movement sets the GMT-hand by jumping in 1-hour steps, the GMT-hand will allways equal the normel minutes shown with the minutes hands. So minute hand and GMT-hand are coordinated, on the asian movement you can set the time only correct when showing the full hour.
Hard to explain, hope I come through to you.
Cheers,
Theo
P.S.: Wow, post # 1 at RWGII