OK a few notes so far.
This particular unit is the G1 model. Much cheaper than the G2, but lacking two things
1) moon lights
2) 3 level programming. This one has two levels (blues and whites)
on the other hand, this is still 160W in a much smaller package than the 20" PC fixture.
One thing of note... I will spend several days figuring out how to program it. There are no instructions.
I still don't have the glass top. The glass shops around here are not open on Saturdays... sigh.
Actual unit info...
This seems to be well built. The whole fixture and power supply/programmer seemed to be machined from solid billets of aluminum. It's smaller than the 10" fixture and much lighter. The lamps are just a few millimeter thick layer of the actual light fixture. The rest is aluminum heat sink. The two fans drawn air in through the side vents, through the heat sink channels, and out the top. The fans are super quiet (much quieter than the PC fixture).
As the top can be easily removed, this should make cleaning a very easy process.
I have some concern about the LEDs on the G1 unit. They are not top-of-the-line CREE units, hence the reasonable price. That means though that the effective life for these LEDs is only about 24 months. (Oh darn, two years before bulb replacement).
I think it will be possible to replace these LEDs and even upgrade them throughout the life of the unit. I used to be pretty handy with a soldering iron.