Just returned from a week in Las Vegas and ate at both E (Jose Andres) and Picasso (with E being first).
The short story is that E had much more refined and thoughtful (?) food.
I would describe E as being more of a food "exhibition" than a typical dinner. The setting is interesting but it certainly is not "posh" like a Prime Steakhouse or Le Cirque, etc. The setting makes you focus on the food at E. Its a rapid fire food show with an exhibition of numerous techniques, textures, and styles.
All in all, we had 23 courses. Many of them were two or three bites. Some more and some were a single bite. There was a lot of liquid nitrogen used. One of my favorite dishes was the "truffle cotton candy with gold flakes." If you like truffles, it was fantastic.
The chef commented that the menu was recently changed a few weeks ago and changes a few times a year. My only critique is that the courses that involved cava or other liquor seemed quite harsh on the palate. The flavors were too strong and the alcohol burn hit quite unexpectedly. Other than that, the dishes were fantastic, as were the chefs.
I would highly recommend making a reservation. I paid $525 for two people which included sparkling water, one drink for my wife, and gratuity. We did not order any of the beverage flights.
A week after eating at E, we had dinner at Picasso. We had the four course tasting menu for $115. I found that the food was very good but a bit clumsy. The foie was served cold and looked like it came out of a tin. The short ribs were good but not great. The desert selection was probably better than the rest. A cheese supplement was available as well.
All in all, I would say that you can find Picasso quality food in any major city. No doubt the food is good, but its not memorable. I can certainly say nothing at Picasso blew me away.
Although I have not yet dined at Robuchon and Guy Savoy, I imagine that they, along with E, are in a class by themselves.