Soy sauce isn't just soy sauce. There are many different styles of quality and flavor, and just like any other condiment people are going to have their preferences.
Personally, I love pure tamari soy sauce. This is the original stuff, darker and more flavorful; it is the traditional recipe for Japanese soy sauce as it was originally introduced from China. Made as a by-product of miso production, tamari soy sauce has far more nutrients and health benefits than the mass-produced flavoring agent that can be found in any supermarket.
Unfortunately, due to production techniques and quality, tamari soy sauce is often considerably more expensive than the standard commercial variety. Even though I love it, I confess that I don't use it when recipes call for large amounts, or when the richer flavor of tamari is just going to be lost in the blend. However, whenever I use pure soy sauce, such as with sushi or sashimi, then I absolutely dish out the extra cash for the better flavor. Tamari soy sauce and some real wasabi make a huge difference.