The biggest problem is that the local teachers and principles at the schools are racist. HQ refuses to accept this is a problem and subsequently won't do anything about it. The foreign recruiters hiring you might not be racist but the schools definitely are.
Chinese staff do not communicate properly with you even though they're capable of doing so.
The pay is low compared to other ESL companies.
No medical insurance.
Unpaid leave.
No room for growth in the company.
If you can kiss arse you'll get a bump up.
There are more cons than pros at this company. There's far better out there.