From what the shop told me, difference between Orient and Orient Star is the dial is also made in Japan + better finishing on the movt.
Price is not such a HUGE diff between Seiko and GS. That would be the Royal Orient i believe but i havent seen any yet in Msia.
When i compare a same model (95% identical) Orient and Orient Star the diff in the movt finishing i dont find too much, just more polished parts.
But then again the diff is just a few hundred.