I have heard of various bad experiences with the Apple Service Centers in Thailand -- both in terms of shoddy repair service (the repaired unit was returned with something else broken), or shoddy treatment (particularly Thais/locals getting treated worse than farang, oddly).
Particularly, I have some experiences of service center refusing to provide warranty service ('must buy new') to users whose broken parts were covered by the Apple Warranty Extension program (i.e. Apple covers them outside warranty), and the service center claiming they need to charge 1,000 Baht 'for checking with Apple', if a particular part or service are covered for replacement (just as recent examples), which is outrageous.
Trying to collect a list of such experiences, the more recent the better (don't bother with the 'farang beaten up at Apple Store, story -- it doesn't apply in this case) - including Mac computers, as well as iPod or iPhone experiences. Needs not be limited to service stores, if you have experiences from retail stores as well.
...and, of course, if you have positive experiences, please share those as well.