As an ex–deli pro with nine year's experience in the Chicago area, I must chime in on this topic. For me, a visit to a new deli requires ordering pastrami. It is the substance that defines the place. Unfortunately, there is only one place in our metro area that serves good pastrami, Max & Benny's in Northbrook, which fortunately is a 25 mile schlep for me. My wife is from New York, so we get to visit pretty often. Here is my take on the question. NY (and Montreal) pastrami is made from brisket. It usually is made without the "point" or "deckel", the fatty tissue that sits on top of the brisket flat. Chicago pastrami is usually made from the plate, the area on the front of the abdomen, which is fattier. Nobody in Chicago cures their own meats anymore; they all use vacuum-packed stuff from Vienna, Hebrew National (not plate), Best's Kosher, etc. At one point in 1976, we actually tried using Schneider's from Canada, which didn't go over very well with anybody. I think that the extra fat in the Chicago version enables a more consistent product, even though always machine sliced thin. I think that New York pastrami, when fatty/juicy enough, will outshine anything in the world. But after dozens of meals at Carnegie, 2nd Avenue, Stage, Ben's, Katz's and others, way too often (even when asking for "not lean"), the tendency (with the exception of Carnegie, which was dripping with fat...eeecchhh) is for NY product to be too lean/dry, but still tasty. My wife's grandmother, from Romania, always ordered her pastrami "cold and fat". She made it to 90 before she developed a blockage!