You down with MSG?

In Portland when I lived on scenic N.E. 82nd Ave (that's sarcasm) there was a pho house not far from my house that I'd eat at sometimes, and I noticed I generally got a weird, unpleasant sensation starting after I'd finished a big bowl of pho, continuing for an hour or two. I thought maybe there was some unusual herb or other they used that gave me the weird feeling, but my friend who ate there with me said, "I bet they use MSG." (Vietnamese Restaurant Syndrome?) Alternately, when I worked in Glacier National Park in summer 2008 we sometimes had these virtually unidentifiable MEAT SLABS served in the employee dining room. They didn't look very good but tasted amazing, and I'd go back for seconds and thirds. The cook later told me they were so tasty because "they have tons of MSG," which according to him isn't really as bad as it's hyped up to be, but rather "just a type of flavored salt." So, what gives? Is MSG really the scourge of Asian cuisine, or not really such a big deal? From what I've read, it sounds like some people who have a special sensitivity to it should avoid it, since in that case it can lead to serious consequences, but that all in all, it's not as bad as it's made out to be. I mean, lots of Asians eat it regularly, right?