Depends on the bike. Olmo, Miele, and Team 3V get San Marco Rolls with no pain so far. I've been trying a Selle Anatomica H2 on the 3V so far ok, jury is still out. I find the most comfortable setup for me is 70's Ideale 90A on the GranCrit.
It's kind of funny. I rode a San Marco Rolls for many years. Then tried one on the 3V and it hurt after only 20 miles. Put a Rolls from another bike on the 3V, same result. Fiddled with position copied from other bikes, no good. Weird.

Then there's this.