I recommend the fireface to anyone wanting a decent soundcard. Simply put it just works as it should, out of the box with no fucking about. The drivers are rock solid and not bloatware, the patch software is easy to use and very powerful and most importantly the sound quality is stunning.
It has a lush bottom end that I never had on previous soundcards (even an rme 9632), its very clear and the stereo spread is great. It can also hit latencies of 1.5ms at 64 buffer with no problems, and even lower at 96 or 192 sample rate.
The support RME give is second to none. They have released about 30 driver revisions since the Fireface came out about a year ago now. They will happily release a driver upgrade for the smallest fix very quickly, sometimes just days apart. Not like some anal companies who wait 6-12 months for a big one job fix all which causes more problems then it does fix (can you say emu?

RME also have a dedicated newsgroup where you can post any issues or queries/questions to them and someone from support with answer normally within a couple of hours.
I use its inputs to route my dj equipment to my speakers which is great for bedroom shenanigans. Its other inputs are patched to the virus TIs analog channels given me those valuble extra 3 stereo streams of TI fun

The outputs I use to patch Live back into my dj mixer where I can bring in extra samples, loops or even songs on the 3rd/4th chan.
In a nut shell. Sturdy bit of hardware, rock drivers and software, awesome support from RME, great I/O and some really nice sound.
Yea it costs a fair bit of ???, but you will seriously not need another soundcard for a long long time
ten