I picked up a Voyager 6 years ago when I was looking for a do-it-all boat. I use it for lakes, big rivers, little rivers, whitewater up to Class III, swamps, fishing, camping, research, birding, and pretty much everything.
Load Capacity and Cockpit:
Through grad school, where I studied fish in river systems, I carried a lot of heavy expensive gear in swamps, ponds, big rivers (Lower Arkansas River), and small creeks. The large open cockpit is great for managing equipment, notebooks, lunch, etc without having to get out and shuffle things. From the seat, you can reach all the way forward and aft to the bulkheads.
For fishing, the same thing goes. There's plenty of space to put things and still access them. I can have several open tackle boxes plus lunch, water, and a camera easily accessible between my knees.
I've taken a couple several-day floats in my Voyager. It can hold more gear than you would actually want to load it down with. It has near the gear capacity of a small canoe, but doesn't have the maneuverability or stability to paddle with 100 lbs of gear. That said, it keeps its stability for extended float trips quite well, and could still handle Class II rapids when I packed it right.
The seat is pretty comfortable for an extended sit. I don't have much padding on my tailbone, so an additional thin pad or inflatable cushion goes a long way. With the footpegs in the most comfortable position, my knees are against the ridges of the gunwale and cockpit edges. This gets a bit sore after a long day, especially in conditions where I brace a lot. A foam pool noodle split open and tucked along the cockpit edge helps, and there's room inside to place hip and knee braces.
General Handling:
In open water, it does tend to weathercock a bit. You won't want to paddle across a big lake without some kind of rudder. Without wind, though, it tracks very straight in most conditions. The moderate keel and moderate rocker together will cause you to turn a couple degrees per stroke during straight line paddling. When turning, I can typically turn about 90 - 100 degrees for each strong sweep stroke with a good lean. For comparison, a sea kayak would take several strokes to do 90 while a creek or play boat would turn 180 - 270 with a single stroke. In flat current (i.e., moderate - fast with no whitewater), its handling peaks. There's nothing more enjoyable than paddling this thing down a smooth, swift river.
Whitewater Handling:
I've had this in relatively tight Class III without swamping. I've done 3' to 4' drops easily, but you have to lean way back. It eddies out surprisingly easily. If you're prepared for the eddyline and get the bow in quickly enough, you can do a full 180 degree eddy out in a pretty small space. Peelouts are a lot harder, so I generally orient myself downstream before getting back into the action. While it doesn't spin, roll, hydraulic, or do any play moves, it surfs like a champ. Because it doesn't 180 easily, I like to run a wave, eddy out, and then paddle back upstream into it. Once you get the bow into a foam pile, it does most of the work for you and pulls you right into position and surfs itself. This boat punches straight through haystacks and standing waves rather than riding up and over them. You will get wet. When this boat gets sideways in a rapid, you will probably swim. Be smart, use airbags, and find one of the few spray skirts that fits. IT'S NOT A WHITEWATER BOAT.
All in all, it's a great boat that has done everything I've asked and surprised me with what it's capable of. Take care of the hull, as it will oil can if you leave it sitting upright on the ground or rack it upright. It's not inherently weak, but it is keeled just deeply enough to bend.
