I've owned 2 Jayco Class C's. I bought a Greyhawk 31DS in 2014 and I was so impressed by Jayco's warranty service that I decided to upgrade to a 37TS Seneca last year. As far as warranty repairs, I have nothing by kudos for Jayco. When a CW screwed up my floor by intentionally cutting the flooring in cresent shaped cuts in multiple places trying to fix an issue on my greyhawk, which I still get hot about whenever I think of what they did, Jayco allowed me to take it to Lazydays in Tampa and they paid to have all of the flooring replaced in the entire RV. I didn't have any warranty issues on the ford chassis in my Greyhawk. It was in for service a few times on the house. There was some hazing on the frontcap that I noticed and Jayco paid for Lazydays to repaint the front cap to.
As for my Seneca, I've had it into Freightliner to repair a leaking rear seal on the rear axle. I took it into a different (non-CW) dealership closer to my house and Jayco was great about paying them too, but the 2nd time I took it back for more work, the dealership told me they would not work with Jayco and that I'd have to submit a claim form to get my money back from Jayco myself. I was nervous about doing that, but I did submit my claim and I received a reimbursement check from Jayco in less than a week.
I can't say I'd never own another brand, but Jayco will get the first and second chance to sell me any RV I buy in the future.