Conclusion, my ass is different. Honestly the c15 felt too wide. Maybe I'm crazy. But I got these sharp ass bones that sat on the saddle strangely. I tried moving my position on the saddle but it wasn't getting better.
So I threw back back on my Arione and it felt like clouds. I'm wondering now why I ever tried switching. Too bad because I really liked the look of the c15 on my bike.

I think I just need some cycling shorts. I was looking for a better saddle because 30 to 50 mile rides hurt my butt, but I think cycling shorts would greatly decrease the soreness.