Air China have 4 Boeing 777-200 which has retrofitted featuring BE Aerospace Parallel Diamond product over the old nasty recline seats, I personally has not being on they yet. But I noticed that Air China is learning things from American Airline in Budget Cutting area by NOT installing IFE in all classes. Due to that I would prefer Air China's old A330s which features Angle Seats. However, Air China has plans to retire old A330s and B777-200s in the near future due to Wide body Limitation by CAAC, also known as Chinese version of FAA.
Air China usually flies B777-200s and Old A330s between seasonal high markets which does not has wide body previously. Due notice that Air China DON'T HAVE WIFI ON BOARD to Passengers!