We were @ The Mirage for a large convention.
During one of the lunch breaks- we hurriedly went to the Carnegie deli. There was already a fairly long line for the lunch crowd. The deli seemed to be able to handle the large crowd; quickly and efficiently. Even affording everyone a seat, by the time your sandwich is ready.
I opted for the lunch combo of half a sandwich, potato salad and a drink for $15.99. The sandwich was piled with too much meat for anyone to really eat. I added cheese to the 1/2 sandwich for $2. The meat was cold, but thickly sliced and good. The potato salad was a tasty rendition of deli/German potato salad.
Service was fast and friendly. Restaurant was clean and had adequate seating.