I was hearing horror stories of TAP but had to fly direct from JFK to LIS so gave it a shot. The plane was in nice fairly new condition. We were delayed 30 minutes going and 15 minutes on the return - so was not terrible. Business class very limited seating and I was unable to get that. One tip I will pass along is get ROW 7 -- there is no premium economy on this plane and with row 7 bulkhead you get to stretch your feet out a little.
Going 6 hours not bad, coming back over 8 hrs not so great. Just a long flight to sit in economy but the staff was attentive and the ride very smooth. The food was decent airline food, nothing special but not horrible. By being in row 7 you get on and off the plane easily so that was a bonus. I had a relatively good experience and found all the TAP personnel on the ground and in the air quite pleasant.