If I'm understanding you correctly, you're saying that regardless of whether you fly east or west, it will take 25-30 hours to get there and you'll be 12 time zones away when you land.

From a jetlag perspective, it's a wash. Your body clock is still going to be 12 hours off when you land, regardless of which way you flew. Your body doesn't know if you're flying east or west.

The things that should affect your decision:
1. Which route involves the shortest travel time?
2. Do the flights heading in one direction depart or arrive at better times?
3. Do you have a problem sleeping on planes if it's daylight outside?
4. Does one route gives you the ability to sleep for 5-8 hours at a time when your body would want to be falling asleep?