Received mine last week. Only have one hung b/c one of the mounting kits were missing a part (screw caps).
Initial impressions
Good:
Sleek everything (housing, cords (which are quite long), power supply).
GCC is fairly easy to use and it truly has more customization than most would even need. Few things took some getting used to. One is nearly every change is instantaneous when you hit "save changes", except for the lighting itself which is a separate project from the rest of the settings (which makes sense I guess).
Wifi worked right away. After you setup this up you don't need to use USB again, but you do have to make a new connection in GCC.
Much more shimmer than my black boxes (which give a very flat t5 look). I wanted more shimmer and was debating Mitras vs Kessil products.
Acclimation feature looks really useful and simple to use. Just set start date & end date & % to start and end at.
Bad (but not really that bad):
Still waiting on missing part. Customer Service is good in that they are responsive, but things are slow and not having the piece for the mounting kit will make it over a month since inital order. 3 business days since I told them about the missing part, just got shipping notification recently).
Mitras get very hot to the touch. You would have to turn it off for a few minutes to take them down if you are running full blast I would guess.
For people wanting to orient it horizontally, you really can't easily, at least with the hanging kit. The powercord is attached to the housing and comes out the back. It would make it hard to balance going sideways. It would have made more sense to have four holes for the hanging kit imho.
Light spill is tremendously more than the black boxes. I initially hung it about 12-13 inches, same as my black box, but I now know it will have to be lower.
I only have the Mitras at 50% right now for acclimation (initially was at 30% but they were significantly dimmer than the old leds, so I figured I was good). I also changed from high efficiency to high power in the settings. This picture isn't really representative of the light power at all and the tank looks like crap, just wanted to show the light spill on the wall so people get an idea of the spread. I think it could do a 36" tank easily if horizontal, or two could do a larger tank than mine (which is 48")