I rode Winchester & Sand Lake once, mostly rode Florence with our Utility ATVs over the course of about 10 years. There are some steep areas to Winchester that a utility just doesn't fit in with very well, but you can get around those peaks pretty easily. Banshee Hill is one of those hills but there are other stand peaks that are about the same. Our kids on 90s struggled more at Winchester with and without paddle tires. I had paddle tires for my Polaris 500 my wife did not, both of us had about the same challenges.
If I had sport quads I think I would have enjoyed them more at Winchester over my utility. IMHO there is more area and places to explore at Florence, and at Winchester you can not ride no the beach.
Sand Dune Guide - Oregon