Anyone have an experience with NI Audio Interfaces?

No experience with NI interfaces, but I was in the market a couple months ago and as I searched more and more I fell into the Focusrite product line and threw this thread out before I made my purchase. Now that I have used it a month I am more than pleased, since it has exceeded all of my expectations.
 
In the past few months I have not seen anyone with negative comments on Focusrite, so I took the plunge, but cannot speak to any other brand.

I picked up a KA6 for my laptop for casual recording use and for playing amp sims, listening to music and whatnot.
 
I looked at the lower end Focusrites, but a number of reviews stated that the instrument inputs lacked enough headroom for unattenuated guitar/bass usage, if that's a concern for you.
 
Seems to be stable for me running Win8.
 
But you'll definitely want to check on the s/pdif out, as there is an issue in that when I tried to run a loopback via the s/pdif i/o but was unable to because it apparently expects to receive a clock signal at the s/pdif in but didn't get it. There was some discussion of this on the NI boards so there was apparently a dumb design decision made. This is not a particular problem for me, but it might be for you, so you'll definitely want to check into it.

been using an Audio Kontrol 1 on my laptop and, until I got firewire sorted so my saffire would run properly, on my desktop machine, for years with no headaches... totally reliable usb interface