I set my preload to about the middle,but I noticed when I had just gotten my bike. The first 5oo-700 miles were murder on me. I couldn't believe any seat could be that bad or uncomfortable.
Then I stopped noticing it. Now I can and do ride all day,tour and have done one 1k run with no worry about seat comfort.This led me to believe that maybe we don't break them in long enough before we change them out?
Now that said,I still want a Mustang for the looks but as a practical need? My stock seat and backrest are just fine..