Alright I'll bite. I have installed about 2 dozen of the "Series" line of Matrix Audio controllers. The "Delta" line is suppose to be a lower cost of the "Series". You only get two choices for the "Delta" - 4/6 and a 6/6 system. The NEW "Delta" and the NEW "Series" line can have any combination of LCD and Taxtile keypads. The system is designed to run on speaker wire, although any TWO wires will do the system. The old line WILL NOT do the LCD keypads. How this system is showing up on online sources is problem just like everything else - its not even available yet. Had lunch yesterday with the Regional Sales Manager and the Rep firm. You buy online - you suffer.