I've eaten hot dogs everywhere from Nathan's in Coney Island to Pink's in Hollywood. A Chicago hot dog with a Vienna Beef dog is hard to beat.
That being said, While the hot dog as we know it may have been invented at Feltman's in Coney Island and perfected at Nathan's, New Jersey is the Hot Dog Mecca. Whether it's Italian hot dogs at Jimmy Buff's, Dickie D's or Tommy's, Deep-fried "Rippers" at Hiram's, Callahan's or Rutt's Hut or "Texas" Wieners at Johnny & Hanges, Goffle Grill, the late, lamented Libby's Lunch, Falls View Grill or Hot Grill, this grizzled old New Yorker has to acknowledge New Jersey.
For the uninitiated, a New York dog is a natural casing dog that is either boiled (Dirty water dog) or grilled and served with mustard and sauerkraut or onion sauce, NEVER Ketchup.
Jersey dogs are also natural casing and are always deep fried. "Rippers" are served with a mixture of mustard and sweet relish and come in four orders of doneness: The in and outer (dunked in the oil just long enough to heat it, but not long enough to split the casing), the Ripper (fried just until the casing rips), the Weller (fried until brown) and the cremator (fried until almost black; it's almost dry inside and has an almost bacony flavor. They're an acquired taste) The dog on the left is a Rutt's Hut weller, the one on the right is a cremator.
"Texas" Wieners are a North Jersey staple. They're generally a deep-fried pork and beef Thumann's hot dog topped with mustard, chili and raw chopped onions. Heavenly, but keep the Tums handy.
"Italian" hot dogs are a culinary triumph. two natural casing beef hot dogs, deep fried until the casings split, tucked into a chewy pizza bread bun, slathered with yellow mustard and then topped with sautéed green peppers and onions, topped again with discs of deep-fried potatoes and topped with ketchup.