I have only been in the CX/KA lounge and by China standards it is a good lounge. By everywhere else's standards, it is quite bad. I believe they now have a simplified internet login process, the old one seemed to be a major gripe for most passengers. All in all, the lounge has a respectable food and drink offering and good seating.
I have not been in the 77 lounge yet. I will be in PVG tomorrow though and I have some lounge buddy credits so I might give it a look see and will report back.