Necrobump!
So, I got one of these recently, hoping it would let me use any USB controller I have with any of the USB based systems I have. They have updated the firmware so that it actually works with the PS4 now, but you need a USB hub and a PS4 controllers for authentication. Kind of annoying, but not really a big deal.
So yeah, setting it up on the computer is a bit annoying, but once set up this thing rules. I've used an Xbone and PS3 controller with it no problem. I even got my 8bitdo SNES controller to work with the thing wirelessly by plugging the SNES bluetooth plug into the Cronusmax. If you load the PS4 profile into it it's even smart enough to map the touchpad click to the select button, which is really handy since I couldn't use my Hori arcade pad with some games since it has no touchpad click.
The bad side I've found is that they really designed this around console controllers. You can use Dualshock 3s, 4s, Xbox 360, Xbox One, and Wii/U controllers with this. Fight sticks made for those systems as well. However, generic USB devices are hit or miss. For example, I first tried the 8bitdo controller with a USB cord instead of wireless and it worked but the button mapping was jacked, and I haven't figured out how to remap buttons yet. I tried the iBuffalo USB SNES pad and it didn't work at all. Thankfully when using bluetooth the button mapping is correct. I'm hoping either my USB Saturn or USB six button Genesis pads work, but I haven't tried it yet.
Getting a dedicated Brook converter is probably best if you only want to use one pad on PS4, but if you want to use multiple controllers on multiple systems this thing is neat.