I came at it from the other direction, but am now VERY glad I ended up with the HD24XR. I was using an older analog 8 track 1/2" machine and wanted 24 tracks, but didn't want to deal with 2" tape costs and maint, but I did want something that would be similar to what I was used to. I got a 24 channel board and the HD24XR.
That of course opened up the world of "in the box" editing, etc. to me. I now use Cakewalk HS2XL and love the combination. I have 24 really good A/D converters, the freedom to mix on an analog board or in the box or any combination there in. I also recently did a demo for a band that wanted to do a "live" recording. I ended up needing 15 tracks of simultatneous recording which of course at 44.1 or 48kHz is no problem for the Alesis. Sounded great.
I do have a 2 channel A/D converter for my PC that I sometimes mix to from my analog board so I can speak a bit to that. I had a mess of trouble getting it set up right in the beginning. Eventually I just started mixing to tracks 23 and 24 on the HD24 and transfering the stereo track from there to my PC via the Fireport rather than mess with the extra converter, which I eventually traded off.
Bottom line, I don't think there's a better way to get 24 really good A/D converters, almost infinite storage space and still be able to mix analog or in the box.
One vote in favor...