OS uses a mix of 342, 343 and 332 on VIE-BKK. Check the *A timetable, that shows the exact dates when what type of aircraft is used. The seats are not lie flat, IFE on 342 is like LH old C, IFE on 343 and 332 is interactive. Food is wonderful.
LX 343 C class is almost as good as LH new C, except that they don't have lie flat seats. LX 344 F is very nice and on par with LH.
SK will start their lie flat C product CPH-BKK this Feb. Check the SK forum for details.