I regularly sit in the exit window seats on this aircraft and on some rare occasions there is evidently a cold draft sweeping across my leg. I fly the LHR-HEL fairly frequently and as it’s only a three hour flight I’ve never any need to use the lavatory, hence my choice of seat. However make sure you ask for a blanket before take off if sitting in the emergency exit window seat. I flew the above route recently but 30mins into the flight when I requested a blanket I was told that they didn’t give them out anymore. I found it strange that the FA had said this as I saw one further down in row 7 or 8 as I was exiting the plane. It’s a very spacious seat as told in the above post, the vacant arm rest makes a difference and that armrest built in to the door isn’t at all awkward, but make sure that you’re prepared if needed!