Sorry Mark - I should have been more specific. I was referring to the characteristics of the punter rather than the qualities of the guide. I think that the sort of person who goes on package holidays is the sort of person who would use a photography guide rather than researching and arranging his/her own itinerary.
I am sure that there are many excellent guides catering for those who prefer not to travel independently.
Fair enough, although personally disagree
(My wife and I are solo traveller / own itinerary people, yet I also use guides).
I don't think its about independence, but about time and efficiency.
I find a mix of both is of best benefit when traveling to new countries with time constraints. Probably the main reason I use them is due to TIME. A guide (the right guide), will often get you to the places you specify at the times you want, in suitable conditions etc and advise what is, and is not, possible.
If you have unlimited, or extended time, then self travel and exploration is certainly great, and I do a lot of it.
I also find, with a guide, or even a small guided tour (targeted at photography, I am not referring to tours for the masses here), I can concentrate on the scenery, the photography and producing images, and less on logistics of 'where next, how long to get there, and where am I sleeping tonight'.
I have done Iceland a number of times now, by both self guided (4WD RV, and 2 weeks exploring, plus a number of road trips), and tours (with Daniel and Josh) and both have been highly beneficial. I would recommend both methods, especially in Iceland.
PS: JS-Campers in Iceland is a great source of 4WD with small RV on the back, works great in the highlands and on the ring road.