Zatarains Pro Boil The Ultimate Crawfish Shrimp & Crab Boil Catering Size Tub 1.5kg

Does this mix contain MSG? The ingredient list only reads a generic 'spices' but nothing specific.

How much would I need to do a boil in a 42 quart pot?

Is this basically the same as the regular crab boil from Zatarain? http://www.amazon.com/Zatarains-Pre-Seasoned-Crab-Shrimp-Ounce/dp/B009K6RAO4/

Do you sell zataraines creol mustard?