I honestly don't know that much about the Chinese Marines. This is basically what I know at present:
1. Though they have a long-on-off history, the present PLAN Marine force has only really been around since the late 1970s'/early 1980's.
2. There are at present two PLAN Marine Brigades with amphibious tanks and a high proportion of motorized infantry.
3. They have been experiencing lately an increasing budget and modest expansion/modernization.
4. The PLA already has 2 divisions (and is adding at least 1 more) trained in amphibious warfare.
5. I am under the impression that PLAN Marines may receive about 3 month's combined recruit and infantry training (I may be wrong about this) - contrasted to the USMC's 4.5/5 months combined recruit and infantry training.
I presume that you know more than me about the PLAN Marines; if you could share a little of what you know with the rest of us, we may be better able to share with you what we know about the USMC and together arrive at a much better understanding of how they compare to each other.