It's not $650 per machine, its $650 for the @ remote box, which can monitor up to 500 connected devices ( 100 devices in Manage mode). The 30XX series machine have the capability of reporting their own meters ect but this is embedded and at no extra cost.
Currently the @ remote box is not bi-directional. It can only send data out. It can not receive. The second step will allow bi-directional capability to do firmware and such
.