JFK used to be Finnair's so called flagship route but unfortunately those days are long gone...it's still a nice flight ex-HEL to JFK, daytime departure with usually nicely paced lunch service.
ex-JFK (after the usual looong taxi..) it's typical ex-US early evening departure..too short east bound night flight to get good sleep which usually means the crew little bit rushes through the service to get lights out as soon as possible..to me AY6 is a difficult flight if the body clock is on EST..getting 2-3 hours of sleep is good achievement..
The JFK Flagship lounge at T8 is quite nice as far as US lounges are concerned.
AY J food quality has been going down the toilet but you might get lucky...seat is good on the new 330s - IFE selection still limited so best bring your own, if that's your thing.