I agree with the above.
Police; easy to carry, great feeling knife. I like the Carbon Fiber version the best. I like lockbacks.
Military: good quality. Nice, large, light knife. Smooth action, solid lock up. There is nothing wrong with the Military, it's just not my favorite. I've had three of them and ended up either selling or trading them off.
I really like the compression lock. I just got a Gunting and am planning on getting a Lil' Temperance. They are a little more bulky than the other two, but I would have no problem carrying the Lil' Temp everyday. That's what it was designed for, a "big, little knife" in Spyderco's parlance.
Can't go wrong either way. I would lean towards the Police, if I had to pick one, as it's a classic that's been around for a long time with a proven back-lock.
Leo