How does everybody determine how good the alteration tailor will be untill they get it done, especially if you can't ask anybody else? In OC, I don't think I have much of an option. Somebody suggested taking to Gary's, one of the most expensive retail stores around. But, that seems like the same logic where that one guy had so much trobule with Barney's. And, do you think that certain people can do tailoring better than others. It seems that Hong Kong can do pretty good tailoring because they were trained by the English. But, what about Vietenamese? Do they also have this tailoring tradition?
I always start by having a simple job done, or taking an inexpensive and/or already screwed up item to the tailor. If they can't handle an easy job they will surely screw up on the complex. But you are really always at some risk. I suggested Gary's elsewhere simply because I thought it might be a good place to start looking. Personally, I always try to go to a tailor that makes custom clothes, rather than store tailors, but some retail places do have good tailors. I think training, and inherent skill, are more important than nationality. I've had excellent work done at one shop by a guy from Mexico directed by the Korean shopkeeper, and if one went solely by national stereotypes you wouldn't think these folks would have been as good as they were.