Right now I have a total of 8 ferrets.  Using only my group as an example,
I would definitely say males are more affectionate, cuddly and accepting of
being handled, etc.  I have 3 boys and they are the ones that act as the
ferret ambassadors for our activities.  They visit my Girl Scout Troop on a
regular basis.
 
Gender does not seem to be a factor as far as ferret interaction.  Though
I usually notice the boys hanging out together and the girls in their own
groups, but everyone sleeps in a huge pile.  I have a very large cage with
2 oversized hammocks, 1 regular sized hammock, 1 'playhouse' hammock and 1
hanging tube.  Most of the time they are piled on and hanging off just one
single hammock.
 
Another thought is that boys can be almost twice as large as the girls.  If
you want a cute petite little ferret, a girl would be great, but if you
like the oversized lumps, go with a boy.
 
You mentioned playing with kits at a store, have you considered a shelter.
Usually a better buy price wise and they enjoy having your little guy in
to pick out a new friend.  Sorry, just my natural reaction to ask about
considering a shelter.  Not that I run one, would if I could though!
 
Good luck,
 
Jen and Gang
[Posted in FML issue 2559]