Reasons to buy:
Endura:
-Back lock, considered by some to be a generally more secure lock design
-Stronger tip
-Some like the qualities of VG-10 over others as an overall better steel (ease of sharpening, edge retention, corrosion resistance, toughness, etc)
-I like the clip better
-Stronger detent
-Ambidextrous lock
-Name starts with an "E"
Military:
-Bigger blade (if you prefer that)
-Some like the convenience of the liner lock over the back lock
-Better ergos (IMO)
-Limited, get one while you can and brag about it to others once they're gone.
-CPM D2, one of the rarer steels use by Spyderco. Better edge retention.
-Name has an actual meaning (what the hell is an "Endura" anyway?

)
If I were in your shoes, I would be in lots of pain and would hate to have to choose (feel the pain) between such great knives.