Z Visa - Change companies?

Hello my name is Ben (I am new here!) and I have been offered a job in China, and my employer will get me a Z visa.

The only problem is that I am not sure if this company is for me, although I am sure China is. I have read that it is impossible to enter China on a tourist visa and convert it to a Z visa once you are there (even with sponsorship). Is it possible however to enter on a Z visa for one company, and then after some time, get hired by a second company and quit the first company? Would I need a new Z visa? Can I do this without returning to the USA?

The idea is that I am not sure if this company is for me, and my employer knows that I am not sure either. I just don't want to have to get to China only to discover I don't like my job and that I have to return to the USA to get a new visa for a new job.

I hope this all made sense! Any help would be greatly appreciated.

i think if you come here with an Z visa you will be able to change company without going back to USA.but you will need to show the police why wants to change.and your new emplyer should give you documents to apply for new Z  visa.