Years ago I had cheese ravioli at a red-sauce place. I had never tasted anything so strong. It was like someone hit me in the side of the head with a bag of baby vomit. (this is a good thing)
Fast forward to 2011. I am making my own ravioli and using ricotta and Locatelli romano. It is the same, the flavor is there, but not as strong as I would like. In addition to the 'butyric acid' flavor that I want, there is also a mustiness (moldy basement) flavor. But I really only want the 'butyric acid' flavor/smell. So I have increased the Romano to a 50/50 Romano/Ricotta mix, and I am still not satisfied.
I don't suppose there is another Romano with more butyric acid and less mustiness? Or maybe it is a function of age? I am even willing to try Asiago. (but I am pretty sure Asiago is not going to work in achieving what I want as I think I've had Asiago before and that is totally different flavor)
The Fulvi DOP Pecorino Romano is much more fragrant, assertive, and flavorful than the Locatelli. And fairly easily available. Alternatively, a good-quality Pecorino Sardo, Pecorino Crotonese (Calabria, usually imported from Sardinia, though) or a Moliterno from Basilicata will have a rounder. warmer, but still sheepy flavor