HCMC -English centres/schools you have enjoyed working for?

We can't be certain but I would suggest the lack of response is indicative of the general state of EFL in Vietnam. No one is willing to name a particular school as "the best".

As far as I know, RMIT (Royal Melbourne Institute of Technology), as an international college,  is the only place that really stands out.

Wall Street English is the only multinational company operating in VN that I know of, unless English First is still around.

Then there are the local corporate chain schools. I think VUS seems to be the longest running of those followed by ILA and AMA. APAX is newly established and "up and coming".

Most of the centres, especially outside the largest cities, are small independently-owned ventures that are usually more relaxed than the chain schools but maybe less organized with fewer facilities.

Finally, there are a number of "international" primary/secondary schools that are not fully accredited but offer an English language curriculum and give teachers a chance to work during the day. In addition, there are a few real IB international schools or those that are somewhere in the process of becoming accredited, such as AIS and SIS, for those with the proper qualifications.

This site has lots of ads:

http://vietnamteachingjobs.com

Hopefully, others can provide further input.