The first impression was actually not very good: Wow, there's not much space here for a 7-hour flight!
On closer inspection, the seat distance was not as bad as feared, but there is NOT much legroom, Finnair economy can't be recommended for the long-legged!
Fortunately, the service improves the overall impression a lot: Really delicious food, lots of free drinks (also beer and wine) and a small snack service at the end of the trip.
Fine entertainment regarding TV, series and music, but I missed the very latest, I didn't find anything newer than 2022.
There was plenty of staff to make it all run easily and smoothly, but they ran a bit on the routine.

BA bumped out to Finnair to return to the UK from Japan. If we thought our flight with BA out had been sub par, this was before flying back with Finnair.
This would be a zero star review had it not been for the staff on board who were all great. The airlines only saving grace.
Where to start with the rest?
Seats. I’ve sat on more comfortable seats on Himalayan buses in India.
These make Ryan Air and other low budget European airlines look plush. Finnair think this is reasonable for long haul 14hr flights. I wonder if any of the management who’ve made decisions on seating budget/ design have ever attempted to sit in one for 14hrs. Doubt they would do it more than once if so.
Food. Can you call it that? I wouldn’t feed what we were served to my dogs. Appalling doesn’t touch it and, again, be interested to know whether the management have eaten this. Not fit for human consumption.
We now await our transit flight in the hope that out luggage makes it to Heathrow. At this point, I’m not holding my breath.

The worst airline I have ever flown 2 meal in13.5 hours the first you could not call a meal The second main I needed a magnifie glass to see the starter Then they fly you with another airline the first or last leg in Economy
Then they never answered any emails of complaint DO NOT FLY THEM

horrible airlines and service! fly delayed almost 1 hour,it's been connected fly, so in Helsinki they doesn't entering me on board to next fly,they said that system it's closed....

If you have kids don’t bother traveling.
They will make you strap down your little baby while she is screaming just to prove the point that she is authority and you are nothing. When asked for extra seatbelt for a baby so she could sit on a lap, flight attendant refused to give one and said she can scream all she wants, I don’t care.
Just horrible that they let people like this work there!