$6000 for 400 watts seems too far off to be right for panels and racks. I use 130 watt Kyocera panels that are $550 each in single quantities. So something like $1600 for 400 watts of panels. Add $550 for the charge controller, $2000 for the inverter, and $1200 for the battery bank and we are getting into the ballpark. Perhaps they mean total system cost.
The weight of the panel is attractive. Those Kyocera panels are 28lbs for the 130 watt size and when clinging to a 45 degree roof with three limbs they are beasts to wrestle into place.
I keep wanting to install this stuff, but I just know in my heart of hearts as soon as I buy it something much better will come out. I've heard a lot of good stuff about on-panel inverters recently, for example.
Maybe a little modularity and standardization is called for. Seems like something that would improve the upgrade ability of users might help increase the number of adopters.
There are parallels in the Audio Electronics industry. At first, each manufacturer did things their own way, and only the hardiest of early adopters bothered with Hi Fi. Then manufacturers adopted standards for input impedances and interconnects, and this made the buying decision less fraught. If you made the wrong choice or could later afford something better, you could swap out a component. Now that the price of building electronics is so low, audio is going towards all-in-one convenience.
When the price of oil goes up everyone expects solar to finally be cheaper - except that when the price of oil (AKA energy) goes up the manufacturing price for solar cells goes up to.
Yup, the first comment mentions that you get ~12x the power from a ~2x more expensive, professionally-installed solar panel.
Still, it's a good start...