Pay is slightly above-average for the greater Guangzhou area. Dongguan is just one endless line of belching smokestacks, the worst that Guangzhou has to offer.
The school is a mixed bag. I have a had some friends who have stayed there for 2 - 4 years and others who have run away at the end of one term. Housing is OK, not great, but not awful.
It is a third-tier, maybe even a fourth-tier university, and thus the students are far from the brightest bulbs in the universe.
You can (mostly) expect to be paid on time, although I understand from my friends that there were a few small delays (October, January, June being the months that stand out in my mind).
There are numerous good schools in Guangzhou proper, why would anyone consider Dongguan? If you like working on the wrong side of the tracks in Detroit, then you will adore Dongguan.
It's not the school that is the drawback here, it is truthfully the micro-area.