And what percentage of people do you "drop"? I imagine once you spend a week with someone you might get attached to them enough that it would be hard to let them go for something subjective unless they were a pretty big asshole.
As far as the "unemployed" part goes, things aren't usually as cut-and-dried as that. Of those five, one was on the verge of being laid off, and one was a student. The other three were gainfully employed. Being open to working weekends with candidates makes this much more possible, though more lengthy.
We're pretty proud of who we are. If your desire to work with us is strong enough, you'll find a way. And if you do find a way under difficult circumstances, it says volumes about your personal drive.
The approach may work for you, but most companies seem to have the idea that they are special, when they really aren't - and frankly most people wouldn't accept your requirements unless they where truly desperate so you will likely have to change your approach as you grow.
Hiring should be at least as important to the team as to any manager. (After all, they're the ones who have to "live with" the new hire.) I can see this working if the team is flexible enough to accomodate the potential employee's current work schedule, assuming the potential is also flexible enough to take on the extra load for a bit.