I have 2 Honda 2000i in paralell and the 6 gal. extend tank. Runs my 15000btu AC and the refrigerator fine. A little bother to set up, but just use one in the AM before the heat comes. They're chained to the landing legs and had no problems last season.
Have since added a 7000watt in the truck bed that has a 30 amp cord from the 5er to keep things cool before we stop. About 4hrs will do it. At the small race tracks we go to around the country, noise is not a problem, so just use that one. Have a homemade genturi exhaust and that helps a lot with the noise but will try the plywood baffles mentioned earlier.
This will be our second season and last year went great, put about 6000 miles on the trailer with my F550 CC LB DW. That disastoris 6.0 has given me 0 problems, all you have to do is service on a regular basis. (and make a few sneaky mods)