IMHO the fact that Asians have been consuming it in huge amounts for over a century, and yet there hasn't been any common health problems linked to it, should be enough of a clue that it's not really harmful...

I've found that restaurants in China in general tend to use a lot more MSG and other glutamate products than North America, enough to give me a little bit of a "high". It would not surprise me that someone not used to it would probably not like the experience. I once went to a "no MSG" one (they exist over there too, because the "chemicals are bad" line of thought is just as prevalent) without being aware of it, and found the food rather bland --- only upon leaving did I notice the signage.