Really? I've had the opposite experience. At the high end, I've found the food is consistently better tasting and better value than the "common" restaurants which are almost universally crap. I've never had a less than utterly spectacular meal at Chila in over 10 meals.Even with the latest price jump Hernan Giaponni restaurant is still a value that is almost impossible to beat not just here but around the world. I've only eaten at ilatina once but it lived up to the hype and I'm dying to go back. I'll miss the delicious parillada de mariscos and the more relaxed and less pretentious attitude of le mistral but Elena is living up to the mantel of excellent cooking.
On the other hand every time I go to a "common" restaurant I get terrible food and its expensive to boot! Speaking of prosciutto, I went the other day out o absolute necessity because I was starving and everything else was closed. I ordered an appetizer, pasta and 1 glass of wine and it came to 120$ and that was with a 20% discount. The pasta which was a shrimp fettuccini came out drenched in far overcooked and over salted cream sauce, the shrimp tasted like they had been frozen and were served with the intestines still inside and slightly overcooked. It was truly disgusting and it wasn't even close to cheap. Don't even get me started on the average parilla here...