We were just at the Pontiac (Illinois) RV dealership open house. I did not pay strict attention to the price postings, but my recollection is that Sunseekers listed as upper 80s MSRP were being offered in the mid to upper 60s. My wife recalls the same. These were white, not full body paint. Models in the 30xx numbers.
When we bought ours there, we got 37% off MSRP. MSRP is sort of a fiction in the RV industry, I think. We got our good price by starting at RVdirect.com, getting a price from them. Then asking midwest dealers if they would meet that price. Pontiac RV actually beat it. I think RVD sells Jayco's too, so you can get a price on both Sunseeker and Jayco from them. They have a dealership in Des Moines, so not too bad if you actually buy from them.
From your bullet points, I would rate #6, Jayco's cap, as the most important advantage between the two brands.
I personally don't think I'd want the tankless heater, but I guess I'd be willing to try one.
You didn't mention the roof. Climb up on each and see what you think. Sunseeker is fiberglass, but has the water puddle catching built up seams above the sidewalls. Then it has a separate piece which wraps over the sidewalls. I don't know what Jayco has. If Jayco wraps over the sides in once piece, I would like that better. In our case, I will just make sure to get up and inspect a couple of times a year. This would not keep me from buying another Sunseeker, but still.
An extra year of warranty could be nice. Certainly can't hurt.
