I had the second year warranty from FR for 150 dollars. My trailer is now 2.5 years old and the furnace seems to have sort of died. I can get a new a furnace for ~800 dollars. or I can visit the RV surplus stores in Elkhart while camping and get it probably at half or 1/3 of that. As things stand now I am glad I did not buy any additional warranties. Especially one which would cost 1,700 dollars.
I am pretty handy, so I am confident that I will be able to fix the furnace myself.
You need to decide for yourself if 1,700 bucks is worth it. Keep in mind that they will do their best not to pay for any repairs as they are in this business to make money. And to be honest, if your appliances start breaking down, that 1,700 will not put new ones in.
If you read all the warranty papers for your appliances, you might be surpried to see that the manufacturers themselves sell extended warranties. If I had done that my furnace would have 5 years warranty for a nominal fee for example. But I was too happy with my brand new trailer to read the warranty cards