I am currently using it as an occasional meal replacement, and for that purpose, it has been great.
I love gourmet food, I love doing my own cooking, and I like eating (relatively) healthy foods. However, I really only want to spends large amounts of time preparing dinner or weekend meals, as most breakfasts and lunches are strictly utilitarian for me. I love the idea of having a food that takes almost no preparation, has a long shelf life, and can be eaten easily on a walk during lunch, or in the car on the way to work. On one hand, I gain a little time this way, but honestly it's nice not having to think about what I will be doing for breakfast or lunch on those occasions.
I don't view this as a complete food replacement, though I'm sure some people do. As a sporadic meal replacement (~5-6 times a week), it's been fantastic.