First started flying as pax 40 yrs ago. Since I live in the North of England, there were far more options than BA, although I used them regularly, since it was company policy for one company I worked for.
I recently reviewed my airmiles tally, and realised that I was about to lose them if I didn't use them fairly soon, because I don't often travel with BA these days. Booked a seat in CW MAN-LHR-MRU.
The outbound transfer at LHR was fine (my first experience of T5), airbridges used for both flights. Boarded the LHR-MRU flight and settled down - or tried to. I discovered I was surrounded by six very drunk Finns, (it's not just we Brits you know!) who had obviously put their legendary drinking skills to good use since checking in at Helsinki.
After about 90 minutes of their disruption the CSD told them that there would be no more alcohol, and apologised to me very loudly, following which they went quieter and eventually slept.
On the return, I was allocated the upper deck (I wasn't about to spend £60 to get the seat of my choice), only to find myself surrounded by a family of four with two young children, who spent the entire 12 hours running up and down the aisle, with their parents making feeble efforts to control them.
Both the long-haul flights were completely full (or so I was told), so there was no option to change seats.
I don't do IFE - I started flying long before it was even thought of, and I've lost the film halfway through too many times to even bother switching it on these days - you can't beat a good book and a pair of (bought) earplugs!
On arrival at T5, I found the signage and staff so poor that I ended up clearing immigration with everyone else (appaprently there is a transfer system, but it's poorly signposted and the BA staff don't seem know how it works). Airbridges used for both return flights. Lounge OK, but it doesn't hold a candle to the VS one.
KLM is now my preferred carrier and my platinum-for-life card is useful for accruing points, and I've been upgraded on both long and short haul flights more times than I can remember, with none of the problems mentioned above. KLM aren't perfect - I've had my baggage mislaid loads of times, but they are always contrite and top up my mileage total witout being asked. BA once lost my baggage for three months(!) and I had a hell of a job trying to claim for missing contents of the half-empty suitcase which was eventually returned to me. I imagine the contents were probably on display at the clothes market in Tehran.
Up here we have such a good choice of airlines, albeit with a change involved on some long-haul flights, (but we northerners are used to adversity
) and I shall continue to avoid BA whenever possible.