We have a DMC at a nursing home and they hae had problems until we put in a repeater. Keep in mind that you can configure the DMC with a USB to serial connection on a laptop but you can't register the handsets. This must be done from the Master phone. Also when you set up a repeater you must have a serial to serial connection. We also put a DMC in for an open warehouse. They love it beause they have no interference. The only thing they don't like is the phones have 5 Notel features programmed on them. You program the list in the System programming under DMC Feature list. The problem is you can't change which 5 features are programmed on them. You can move them or delete them but you cannot, for example, take off Call Park and put on VM Transfer because VM Transfer is not part of the original 5 features. The DMC works in applications where you don't have alot of interference.