A lot of good points and viewpoints are being presented in this very interesting thread. Several things come to my mind including that each of us has different skill and comfort levels to make repairs ourselves. We each use our rigs differently and some are older than others. So, each of our viewpoints is important.
I would make my "2 AM sweaty palms" comment: if it is something that is going to worry you and take away your comfort and enjoyment of your RV, don't do it!
Personally, I am totally comfortable without a warranty but I think there are a lot of us that should have one to fully enjoy worry free travel. I enjoy the maintenance aspect of our rig and repairs are simply a part of the hobby for me. I enjoy working on the thing! I have been exceedingly fortunate in that I have taken only one rig in all my years of rving to a dealer for a repair. I will not touch the chassis but that is another matter. I do take the Ford part to a local shop I have been doing business with for thirty years and they have two bays for RVs under 30 feet to do chassis work. I took the PC to a local independent rv repair shop to have a towing/braking system installed because I don't know come here from sic 'em about doing that and didn't want to risk my life or someones life on my Billy Bob installation.
A service warranty is simply an insurance policy, no more and no less. You have to read the fine and very fine print and think about it before you purchase. Folks often get surprised when they find out a need is not covered under the extended warranty.
The risk of not having a warranty is quantifiable. How many years have you had your rig, how many more do you expect to keep it, how well do you maintain it and how many miles do you drive it? How much out of pocket risk can you assume? If for example, you had a $800 a year premium and hadn't used the warranty in five years you could have saved four grand. Personally, I have a $1000 deductible on all my insurance policies. In essence I self insure for the first grand. To me, insurance is to cover the "biggies" I can't afford or control and the liability that is always present. Having spent fifty years in finance, I finally figured out my Finance 101 professor was mostly right: fear and greed where money is concerned are the only two emotions. My greed just keeps me from turning over those extra bucks to an insurance company. My fear always causes me to wonder if I am making a mistake by not doing that, so we are back to the first question: what is your PERSONAL comfort level?
Just my thoughts since like a lot of us I got us an hour earlier today

Paul