One of the best guitar sounds i ever in my modest home studio was thru the mkII into adobe audition using a soundblaster sound card. This was not an analog recording however, because it never touched the tape, just went thru the mixer section. This was years ago, and i have upgraded, but i kept my tape machine. I used it over Christmas to transfer some of my fathers older cassettes, into protools 7.3, using the mkII's direct tape outs, wich means it goes from tape directly into the computer, bypassing the mixer section. i routed it this way to preserve as much of the original recording as possible, tape hiss, flutter and all! Be careful when transferring commercial, or finished cassettes, to turn off the dolby NR on the unit, otherwise it will sound quite strange. (which could be a cool effect if your going for that) If you plan on doing more than 4 tracks of analog, you have to sync up your machine to a code, the manual says how to do it and what you need. Otherwise your tracks will not be lined up like the were when you recorded them, because a tape stretches, and the playback section doesn't play exactly the same speed the whole time. It is possible to use the machines mixer when going into the computer, by using a combination of main/monitor, or Headphone outs/ and the cue/efx switch and still get four individual tracks into your computer. gotta check your manual because i've forgotten exactly how i used to do it.
As far as sound quality goes, i was very pleased. I a/b the feed from the tape and the recorded digital copy and they were quite close, but the digital version did lose a little of it's girth but not much. I would expect high end converters would preserve this much better. But for a $500 interface (fw 1814) I was happy, so was my dad. It was refreshingly fun to record on the mkII a few months ago when my computer was down, and i forgot just how good this little machine sounds, for what it is. In fact my friend liked the results he got on that, over the digital set from a few months prior (he does folk style).