Just returned from Vietnam and Cambodia, and the comparison of Vietnam Airlines on my trip with BA was, I thought, quite illuminating, especially as I have only recently had an underwhelming WTP experience with BA on return overnight 12 hour flight to South Africa. So, here goes:-
Long Haul:
Out: (LHR-SGN) Business - no wow factor, but nothing to complain about either, other than use of a pay to use lounge at LHR, which is not unreasonable, given only 1 flight a day. All aisle access as is the norm now, unless you are unlucky with BA. Boarding better, without the scrum you seem to always get at LHR with BA these days.
Return: (HAN-LHR) Premium - this was the real eye-opener. VA prem seat was exceptionally comfortable, and I got 7 hours unbroken sleep, whereas on the two BA flights I managed around 3 hours broken sleep on each leg. Much greater recline, wider, 42 inch pitch (think BA is 38). Soft product (food, service) was better too.
Short Haul (3 x 2 hr sectors)
Business: Two of the three were on 787s, so Business seat was a flat bed! The third had proper business seating (2+2) on an A321, in comparison to BA's block the middle seat arrangement.
Economy: Proper snack (eg chicken roll), and choice of beverage including alcohol, in comparison to b*gger all on BA.
There didn't appear to be any charges for seat selection either in any class, in contrast to BA.
I think it just reinforced my view as to how much BA has declined in recent years, and maybe it's a symptom of many "full service" flag carriers too within Europe.