Naaah - the 342 is slow, but not
that slow. My guess is that the companies in question have taken the prevailing winds into account, so an E-W passage at mid-northern lattitudes will take longer than the W-E passage.
If you do not want the sun in your eyes during the long flight, make sure you book a seat on the right-hand side of the aircraft for the outbound trip and the lefthand side for the return trip. When going east, the opposite applies - POSH (port out - starboard home)
Brgds
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