I think it depends on the pheasants attitude and how much space they have. If it is a very large flight pen and they both are accepting of others then perhaps yes. At this time my Swinhoes are in with a young pair of Lady A's until I get a pen built. My young male Swinhoe grew up with them and is fine, the new trio is bossy and will chase them some. I have a lot of perches up high so they can get out of the way. I don't know if I'll chance it during breeding season though. They say that about Silvers too, but this past breeding season my two males were together with two hens and were fine, I hatched a lot of chicks too. They are both easy going males.....
They are basically quiet as far as most pheasants go. They will tlak to you and drum A LOT but its not obnoxious by any means. I suppose it depends on the birds. My Swin males are pretty aggressive during breeding season.