Plug and play without a hitch.
I only had to really change a few settings within the menu to get things to how I wanted them. Otherwise, on both PC and the SuperStation One, I had basically a plug and play experience with no hitches. I tested out my OEM SNES, Genesis 6-button, GameCube, N64 and Virtual Boy controllers. All of them worked perfectly. I imagine the firmware updates will only make the experience even more seamless as time goes on.
As far as latency goes, which was a big draw for me, I have no real way to test the actual latency available to me, however, I do some speedrunning, and from the best that I could tell everything felt nearly instantaneous. Very impressed and happy with the results.
If you're on the fence, just buy the thing. It's really not all that expensive for the value that you get if you have OEM controllers that you'd like to use via USB.