The insurance is probably not worth it.
That said, I was worried about the 4 speed transmission in my motorhome, and I bought the insurance for $2,500 or so on my then new 1997 Fleetwood Bounder. I declined the first 'offer' of $4,250 insurance, and when I was getting the RV financed, I had time to think about the insurance, and the counter-offered full coverage of all appliances, lubricated engine and transmission parts (not including anything to do with the brakes, air cleaner, ect).
Well I ended up on the winning side of that insurance policy. They replaced several of the jacks when the main seal went bad at $750 each installed (my deductible was $50 each time we brought in the RV for whatever went wrong with it).
Also we had a rear axle seal start leaking and that caused one tire to blow out, because the rear axle fluid leaked on the tire. Tire was not covered, but the axle seal was. Brake pads where not covered, even though they soaked the brake pads with oil when it left the repair place (the pads where smoking a LOT when we brought home the RV, but not when we took it in with the leaking seal) because we would not pay $500 for them to install $73 brake pads on the rear axle. I installed them myself.
Nothing else went wrong with the motorhome while it was within 5 or 6 years old.
I bought insurance on my Honda CRV, and nothing went wrong with it either. The insurance has a huge mark up, so ask the dealer if they can provide coverage at a lower price. Probably they can. It might be worth say $850 for 5 years. THey really are only going to cover 4 years after the warranty expires for the structure and other things. Perhaps 2 year for the refrigerator after the warranty for it expires.
SO is it worth it? Can you put the $850 in the bank and use that and the interest on the $850 to pay off any required repairs? Certainly not worth the full $1,900 that they are asking for the insurance! Probably the salesman will get $200 of that total, and the dealership another $400 of that as pure profit!
Good luck, Enjoy the new RV and have fun camping!
Fred.