I have never eaten one nor will I just because they sound gross. I was curious what they were made of so I checked the McD's website.
McRib Pork Patty:
Pork, water, salt, dextrose, BHA and BHT and propyl gallate and citric acid (preservatives).
McRib Bun:
Enriched flour (bleached wheat flour, malted barley flour, niacin, reduced iron, thiamin mononitrate, riboflavin, folic acid), water, yeast, high fructose corn syrup,
contains 2% or less of the following: salt, corn meal, wheat gluten, soybean oil, partially hydrogenated soybean and/or cottonseed oils, dextrose, sugar, malted barley
flour, cultured wheat flour, calcium sulfate, ammonium sulfate, soy flour, dough conditioners (sodium stearoyl lactylate, datem, ascorbic acid, azodicarbonamide,
mono- and diglycerides, ethoxylated mono- and diglycerides, monocalcium phosphate, enzymes, guar gum, calcium peroxide), calcium propionate (preservative), soy
lecithin.
McRib Sauce:
Water, high fructose corn syrup, tomato paste, distilled vinegar, molasses, natural smoke flavor (plant source), food starch-modified, salt, sugar, spices, soybean oil,
xanthan gum, onion powder, garlic powder, chili pepper, sodium benzoate (preservative), caramel color, beet powder.
Crinkle Cut Pickle Slices:
Cucumbers, water, distilled vinegar, salt, calcium chloride, sodium benzoate (preservative), natural flavors (plant source), polysorbate 80, extractives of turmeric
(color).
http://nutrition.mcdonalds.com/nutritionexchange/ingredientslist.pdf
And I included the link too. The bread is what was scary to me. I do eat Mcdonalds once in a great while. My niece works there and she still eats it so I figure it can't be that scary.