What stability problems do you have? I never got it crashing (except once because I had left their driver auto-update running & they updated with broken ones).I have an x-fi card in my opinion it doesn't hold a candle to my steinberg MR816 fire wire interface in terms of low latency and stability.
As for latency, it goes down to 2ms.. but anyone sane wouldn't go under 5-10ms, whatever the soundcard (for other reasons than the soundcard).