I arrived in T3 on opening day in the morning on CA from Hong Kong. Besides having to park at a remote gate and be bussed to the terminal, I was very impressed with how smooth everything ran. I have to give them a lot of credit, the train was quick enough, immigration was a breeze and the luggage arrived within a few minutes. I didn't realize that we would be arriving on the day of the opening of the new terminal and when I found out when checking in at HKG, I imagined chaos as I experienced on the open days at HKG and MXP, but I don't think anything could have been better for an opening day. It seemed like the terminal had been open for a long time already.
2 days later took CA again from PEK T3 to SHA. Again, everything was a breeze except that there were so many counters to check in for CA and it was difficult to find where to check in since it seems different destinations have different counters to check in and it was not clearly marked. I was directed to 3 different check in areas before someone would check me in. Even then it was not the area for *G passengers but since there was no line it didn't matter.
Since traveling Y for a domestic flight, no chance to sample any lounges.
I did see the UA plane parked next to an LH plane in the last gates almost as far as you can get from the check in areas.