I-130 I-508,I-566 and I-485 ,
-Yes, you can file all of these forms (plus AP/EAD application if you want) at the same time if your parents want to get the GC within U.S.
You also can file I-130 first and file the other forms after the I-130 is approved.
I-508,I-566 and I-485
( If I still need to file I-130 ? )
And, this will have a delay of the case processing,
-I do not see any delay compared to the other people.
but should still be much faster than Consular processing, right ?
-Your parents also can choose consular processing to get the immigration visa in China. If so, they do not need to provide I-566 and I-508 because they need to go back China to get the immigration visa.