cheapest i've seen is the 24 inch for 1300 and the 48" for 2200. I saw the display on the zero edge tank at NERAC and thought about it for my 120 for about 3 seconds. Even if you can get past the 2 thousand dollar price tag it just hasn't been around long enough for me to try it. It is definitly worth seeing though, the sunrise, sunset and moon phase options are amazing.