Is this a risky move?

A friend of mine, a 2nd year (will be her 3rd yaer in Sept. )high school math teacher, is getting a very nicer offer in an international school in China, teaching A level math--a British standard HS curriculum, and the working environment is much better than her current one, i.e. less students in class, motivated students, etc.

She don't know if she should take the offer. She worried that once she leave the US teaching system, it is hard to get back in. it is very difficult to find a teaching job, and she is not sure, that if in case she want to come back to usa, can she find a job or not?

Are there any teachers here can give your opinion? would her oversea teaching experinece valuable and make her more competitive, or she should wait till her get more experience in the US?

It is always very hard to find a teaching job or it is because of the economy?

Thank you very much.