Manfrotto 334B, 685B monopods — comments please.

[Gregory]

I'm interested in getting a monopod whose height can be adjusted very quickly and conveniently with one hand while the other remains on the camera. the Manfrotto monopods look pretty good. has anyone used either of these?

685B NEOTEC MONOPOD W/SAFETY LOCK

334B AUTOMATIC MONOPOD BLACK

I'd be using a Mark III with any of the following lenses: 24-105, 70-300DO, 400DO

in addition, I seem to prefer Gitzo but I can't find anything similar in their catalog. does anyone know if Gitzo makes similar monopods?

regards,
Gregory