Personally, I think the Maxpedition Condor II is a better pack then the Falcon II. The Falcon II is a good pack, but if your going to be on a full 2+ day hiking/camping trip, the falcon II seems a little "small".
A lot of it depends on "what" your going to be doing with the pack, hot weather hiking/camping, or cold weather, or somewhere in between.
I have never used the Voodoo Tactical Level 3 Assault Pack, but I have used both the Falcon II and the Condor II.
The Condor II seems like its built for shorter people. The Falcon II seems to be a little longer and wear a little better then the Condor II.
The Vulture II on the other hand is a larger pack - but one of the problems I had, my nylon straps would not go through the loops on the bottom of the pack. That means that I could not strap anything to the bottom. I sent an email to maxpedition about this, but never heard anything back.
This video video about the vulture II was made before I discovered the loop problem