I guess that depends on your definition of large.
My LS box scans approx. 2500 computers, 115 copiers, 60 WAPs and at least 100 VLAN'd switches across 40 different IP ranges, including VPN users. We noticed no bandwidth issues or switch config problems. We've been running this box for several year now. Our VLAN setup is basic though. One for workstations and one for VOIP hardphones.
Our agency HQ also runs an LS box for the entire agency. More than 10000 employees. However they do not scan non-Windows devices. They are only concerned with workstation and server info.