I think it comes down to grip style. I'm a big fan of the usual Spydie shape that's almost pistol-gripped, with a very curved spine. This is very natural for a saber-grip and attractive, too. The Starmate stands out next to the in-house Spydies by having a very "straight" shape.
Setting that aside, I think they both have merits but I prefer the Military. I like the great geometry of a full flat grind, prefer the larger blade (though with its huge handle the blade could still have a further 1/8"-1/4"), and the finger choil for "choking up" is super. It also beats the Starmate hands down for deployment speed - it has an extra-large hole, a grip taylored to "drop" opening, and an opening arc of about 160-165 degrees. By contrast, the Starmate has a smaller hole partially covered by one scale, a grip that clearly doesn't consider this opening method (it's taken almost directly from the stud-bearing Starfighter), and a more awkward arc of almost a full 180 degrees. I modified my Starmate for better drop opening and a grip I like better, but overall I'd still prefer the Military.
In the Starmate's defense, it is smaller and has a very beefy tip. It also has a very deep hollow grind that some folks prefer.
Both great knives, anyhow. I'd take either over my Wegner, Police models, Endura II, etc. Only the AFCK really competes, IMO.
-Drew