I have the 5x bay eBOX-R5 of DATOptic. Base on the look I think they combine 2x of my box(ebox-r5) in one.
and I'd used more than 20's controllers that they use in the box that you're looking at
One thing I love about it, there is no drivers - just plug in and in seconds, there is it
I can create a raid5 less than a minute, not like other taking days