I've had great pies out of most of the big name Italian brick ovens: Stefano Ferrara, Forno Napoletano, Cirigliano Forni, and of course my biased personal favorite - Mario Acutno (Forno Autentico). I don't think there is a lot of performance difference in this group. If you want the Italian name with the most ovens in service in the US, it's Stefano Ferrara. As for cast ovens, it seems like the most common name I've seen is Wood Stone. I've had some good pies out of them too.
CL