It seems that lately I have been spending a fair amount of my time sitting in a harness. So I thought I should review the three harnesses I use and explain why anyone would require three harnesses.
My regular climbing harness is the Petzl Adjama.

It's a size med and the waist belt, at it's most snug tightness, just fits my 30-31 in. waist. I like the Adjama because it's light weight, well vented for the warm climates and has adjustable leg loops for when I find myself in heavier clothes for snow and Ice. It also has 4 bomber wide gear loops. I almost never use this harness in rigging for my photo shoots. It's ok for a short hang at a belay, but not comfortable for long hangs.
For that I have two other harnesses. my light weight rigging harness is the Black Diamond Big Gun (about $115 US). There's a third party video review (here) .

Besides being light this harness also stuffs into a small stuff sack making it my choice for an expedition and climbing rigging harness. It's well vented, has 7 gear loops (you can never have too many I say and none of these gear loops looks like they will break) it has leg loop adjustments (important for a truly versatile crag/mountain harness) and has the ever important wide belt and wide leg loops for comfort during long hours of hanging on a rope or a belay. The harness also has two belay loops. Thedouble belay loops are really important for rigging. As they make it easier for me to organize my harness rigging. I like having the safety daisy of my upper ascenders on a separate belay loop than that of my lower ascender (or Croll if I am ascending a free hanging rope). The belay loop that I use for my lower ascender on is also the loop I use for my Grigri or rappel device. I find it's easier to do the change-over from rope ascension to rope rappel if the upper ascenders safety line is separate from the loop the rappel device is clipped into. The second loop can also be used if you are using a directional rope to pull you to the side for a photo angle. But if I am doing this kind of rigging and if I plan to be in my harness all day I would much rather take my heavy weight harness.
The Petzl Navaho Bod Croll ($450 US) is my heavy weight choice for a rigging harness and It's the latest addition to my harness collection. I use this harness for vertical rope access, that is rope work where I will rarely if ever touch my feet to anything but my ascender feet loops. This might be for caves, giant trees or to shoot pics of someone sending a project on a massive over hang, In the Navaho Bod harness I have the smallest size the Navaho comes in and I can tell you I have every strap done nearly as tight as they will go including the shoulder strap. Those smaller than me, I am 5'8 with a 30 in. waist, will have to wait for Petzl to come out with an extra small version.

As you can see the Navaho is both a waist and over the shoulder harness set up. It comes in about 4 configurations, my harness is the total package called the Bod Croll) The shoulder set-up on my Petzl Navajo comes integrated with a Petzl Croll ascender. This is a perfect set-up for ascending free hanging rope. My harness probably weighs well over five pounds when it's fully rigged with my Petzl ascender, Croll ascender, 3 locking biners and my 12 mil 20 ft. directional line and ART positioner. What's great about this harness is it is a no compromise system. You can do anything in this all day long. Every part of the harness is tested to full strength. The harness has a main front D-ring as well as directional D-rings on both sides and back of the waist harness and a D-ring on the back of the shoulder harness. If I have a complaint it is that the main D-ring in the front will not easily fit 3 large locking biners. The only reason I would have three biners up front is sometimes I like to keep my positioner in the front D-Ring . A big bonus is you can make this harness much lighter because you can remove the shoulder harness if you are not planning to climb vertical ropes. In this way the harness can be used as a waist system only. The waist harness has several strong gear loops that I have no worries about clipping in gear bags with expensive cameras and lenses. The leg loops are adjustable, the gizmo that Petzl uses to adjust the leg loops is a really trick device, but I find it to be bulky, heavy and way over-built. To get in the harness you just step into the waist and leg loops and then pull together two buckled straps that cinch the harness around your waist. Getting this harness on is fast and I can be clipped into a vertical line and ascending safely in seconds. If you need to add a jacket it's easy to get out of the shoulder harness to put on a jacket while still clipped to the rope. I first used this harness for a recent assignment for National Geographic and during the two weeks on ropes I only used my Black Diamond Big Gun harness once.
So that covers the three harnesses that I like to use. Every harness is a hugh improvement over the old Petzl Jump harness I used to use.