Having just taken the SQ flight EWR - SIN -BKK (RT) on the 340-500, I can't praise it highly enough. Great flight in Exec Economy, lounge area, good pitch, great schedule with just enough time in Singapore for a morning swim at the outdoor pool in the transit area before getting the Bangkok flight. Used my United miles for the trip. Before this flight, I had only ever flown to Bangkok on United or Northwest via Tokyo), and don't think I'll ever be able to suffer like that again.

I have only taken Thai on short haul flights, but find their service far poorer than SQ.

I agree that China Airlines has a very poor safety record. They are one of the few long haul carriers I would avoid for safety reasons.