If it did indeed "cover everything" it might be a good deal, but it most assuredly does NOT! Read the contract language - there are exceptions galore, starting with any "normal wear & tear", any upholstery, any body parts, most electronic gear, etc. etc. etc. It is nothing at all like the manufacturer's original bumper-to-bumper warranty that "covered everything".
National Interstate specializes in RV coverage. And there are agencies that specialize in finding cost effective insurers for RVs, e.g. Gilbert, Blue Sky, The Tobin Agency, Explorer RV, and Miller. Just to name a few well known ones.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL