I have both knives. I'm wearing an Emerson Commander at the moment. I'm not planning on "killing dudes," but I am living in a combat zone, and it is a primary consideration of that knife.
I've got several other Emersons here, and a CQC-7 goes with me each time I fly, as does a CQC-13. I carry a backup Commander.
I just recently bought a used Military online, and it was shipped to me here. I can't say enough good about it. I really like Emerson products and they've followed me all over the globe many times over. I've carried them and used them on every continent but Antarctica. My Emersons work hard and I trust them with my life. I'm very impressed with the Spyderco, however, and it's going to be a constant companion, too.
The Spyderco Military is every bit of what I expect out of a Spyderco. Some very thoughtful aspects of it's design really appeal; it's just a well made, great knife. It's in my pocket right now, as is a Scorpius.
If you can avoid the counterfeits, you can get a good deal on an Emerson on Ebay, sometimes. Get one.
I'm not a big fan of the CQC-7, though I own several. I reall like the Commander, and I like the CQC-15. Great knife. If size is an issue, one of the best pocket knives I ever had was the mini-commander. I lost it not long ago, and it had been everywhere. Literally. It was a well beaten, well worn knife, and locked up solidly, sharpened to a dangerous edge, and was as trusted as any knife I own. It was replaced, after being lost, by the Commander I'm wearing right now.
Other said it, I will too...get both knives. I very much doubt you'll find disappointment with either one.