How expensive it is, and how it compares to a TS meal, really depends on what you order and how filling the portion of the items you order are.
You can go the route of a PP who purchased the most expensive for what you get items (the filet and cheddar cheese soup) or go for less expensive and more filling options. I'm thinking of the waffles in Belgium (both sweet and savory), the curry chicken from Singapore (I couldn't get enough of that), the fisherman's pie from i think Ireland, the ravioli from Italy I think. There were lots more tasty and filling items available that I can't remember right now.
Last year, another site had photos and reviews of items from all the booths, including the website owner's opinion on whether he thought it was a good value based on what you got. Hint: he didn't think the little bit of cheddar cheese soup was a good value. I ordered it anyway, and have to agree.