Somewhere around the CNC Edelbrock head. I have a set here, but they're on an engine. However, I use the same Cometic intake gaskets for them as I do some of the larger CNC ported Edelbrock heads. They would not work on a small bore, but if you have a larger bore, they work really well, especially on the exhaust side. Usually 340-350 cfm on the intake and 260 on the exhaust.
I flowed a set of Barry's heads here, as I purchased them for a customer's 511 inch build. I bought a CNC ported set and asked Barry to flow them before he sent them so we could have an idea of how close our benches were. Barry used an SF600 from a local shop to him, and I used an SF600 from a local shop to me. On the exhaust side, we were within 3-4 cfm of each other if I remember correctly. The spread was a little more on the intake side, but I tried several different bores, as well as different entry plates and valve prep.
I did a write up on the other forum and can cut/paste if anyone is interested.