There are a zillion posts on here and www.irv2.com
answering this question.
No one can answer for you.
It's not "like an insurance policy
" it IS
an honest to goodness insurance policy. It's no warranty.
You are gambling that your RV will have a lot of "covered" repairs. They are gambling that you won't and that if you do they can figure out a way to disqualify their having to pay for it.
Keep in mind, to get a repair under a service contract you have to take it to a place that will honor the contract, you have to get everything estimated and approved BEFORE anything can start. And, they write these contracts in such a way that THEY get the say on parts and what they will cover and what they won't cover.
However, if you decide to get a service contract it's best to not buy it from the selling Dealership. Those are always over priced, over promised and under performing.
Due to the age and mileage you might consider a chassis only policy to cover the expensive diesel and drive train items.
Good luck with your decision.