If you want 60hz 4K I recommend a monitor 37"-40" because any smaller and the Windows UI and websites becomes so annoyingly small and hard to read. Also windows ppi scaling is pretty shoddy compared to OS X. This thing has about the same ppi as the 30" 2560x monitor, only the extra pixels were used to make 10 more inches of screen space.
Sitting at normal distance, the screen completely fills your view, sort of like an oculus rift. Typing is ok since its text is the same size as any other monitor, only there's more screen space. Games are awesome as I've never seen them this big and clear, it's like looking through a window