Peter, I think its a case of horses for courses. If I am in a place where there is room to set up my tripod without impeding others then that is what I use. In situations where there might not be much space etc I'll use my monopod. I also carry the monopod when out cycling as it is lighter and easier to stow on a bike. See the Wales and Castles thread for examples of photographs taken using a monopod.