Not sure either as I don't have the AS version, but I did pick this up yesterday.
From what I can tell the XP product has both Marks, whereas the AS version only is the Mk. II. Also, the AS version seems to have a weapons bay.
The models, textures, sounds and VC are spot on and nicely done. I'm not so sure of the flight dynamics in that I've had to reduce the sensitivity of the elevator and increase pitch stability. This might be because of my older controller.
BTW, I'm flying the FS9 version on an older Pentium 4 with 128 Mb graphics and FS9 graphics about mid range. No major FPS issues, but the VC does take awhile to load. I also noticed that the panel.cfg doesn't contain any entries for the VC gauges, so my guess is that they've built it into the models.
The 60 page manual is nice with a nice history and details on the a/c. I'm still not sure if there are any extra key commands I'm missing or if I've found all the annimations features - meaning, if there is a weapons bay for the Mk. 2, I can't find it.
The other thing I've encountered is that you cannot use the mouse on the gauges if you're running F1View. With some of the gauges you need the mouse wheel, and if you have F1View it uses the mouse wheel for zooming. :brick:
--WH