They are both great for different reasons.
Eroica has always been a bit of an organizational mess, this year more so than prior years. However, I've come to expect that so it doesn't bother me and I compensate by being relatively self-sufficient. On the other hand, Eroica also has the concours, multiple routes, amazing coastal vistas, a ton of interesting people, and always a great spread in Cayucos.
Cino is nice because it is small, super friendly and local, and has quirky aspects like the bacon lady. I hear that it has great rest and food stops too but I haven't made it that far yet. Perhaps this year.