Welcome to the forums! I think you'll like it here...as long as you're not too thin-skinned.
If they heat-treat the D2 properly, it should hold a much better edge than the stainless (they use Sandvic 12C27 I think). I would the think the toughness would be quite comparable, but 12C27 may be a tougher. Corrosion resistance is obviously an issue (12C27 having the edge), but D2 is still quite corrosion resistant.
I think Ka-Bar has a real winner with its D2 USMC fighting/utility knife.
I would buy the D2 model without any doubt! I have used a number of Ka Bar knives and own a few. I decided to pass up on the 12C27 range. I found the rust resistance of my D2 model quite adequate with proper protection and the edge holding is in a different universe. I also found the 1095 steel range holds a very good edge and is amazingly tough. Go for the D2 model, I did.