I have a Bogen 3249B with a small ballhead on top and love it. It has 3
sections and therefore goes short enough to fit inside a day pack or a suitcase.
I've gotten it into many public places that exclude tripods. The only place I
ever got told I couldn't use it was the United States capitol building. Even
there I got it in, but some guard stopped me when I set it up. No one complained
at the Lincoln Memorial or the top of the Washington Monument, or in the Bath
Abby, Bath, England. A monopod is especially good when combined with a bean bag.
For example, at the Lincoln Memorial, I shot down the capitol mall by using the
monopod and leaning the camera body against one of the pillars with a beanbag
between the pillar and the body.
-- David Jacobsen
I use a Bogen 3016 monopod with the 3229 swivel head with quick release (costs
about $50 as a combo). It comes along with me when I want to enjoy walks through
Boston. When I want to suffer, I strap the 3221 to my back.
I used to use a Kaiser small professional ballhead. The swivel head has three
big advantages (in addition to costing 1/4 what the Kaiser cost...):
It's much shorter than any ballhead, hence more compact to carry and better
balanced when shooting verticals.
There are fewer degrees of freedom than a ballhead, hence less to think about
while shooting (use the swivel to switch from horizontal to vertical, adjust aim
by moving the monopod, very natural).
It uses Bogen's small rectangular plate quick-release, which is very sturdy
and much more compact than their huge, ugly hex plates (I used to use Bogen's hex
plate quick release system on the Kaiser, which made it HUGE).
I can hardly stand using a tripod without quick release, but I'd go insane
with a monopod! Having the quick release helps you resist the temptation to carry
the camera mounted to the monopod at all times, which can be dangerous, as I
found out the hard way: If you bump the end of the monopod and lose your grip, an
extended monopod is a VERY long lever arm that will slam your camera into the
ground with great force...