I tried out my Hobie Oasis this past weekend in solo mode, and I thought I would pass along a couple of comments.
I filled up an old 5 gallon plastic gas can with water and put it up in the front - it fit almost like it was designed for it. I put the plastic drive plug in, and strapped down the 2nd Mirage drive up there. The bow was touching the water all the way to the front, so that amount of ballast was just about perfect. (For reference, I weigh about 210 lbs.)
The Oasis pedaled just as well solo as double, and also paddled fine. Come the end of the day, I was easily able to outdistance my buddy in his Tarpon 140. The extra ballast weight was not a liability. I really liked having the front cockpit area free for storage. My buddy's yak has a huge rear deck, while my rear deck barely has room for a milk crate. But with an empty front cockpit, my front "deck well" is every bit as large as his rear well, and more accessible, since it is front of me. I was able to "crab walk" on the rails over the top of the pedals to access anything up front. The water was calm, so in worse conditions pulling the drive may be advisable to get up front, but that is relatively easy.
Loading the Oasis by myself is easy, too. I rest the stern on some padding a few feet behind my car, with the yak at a right angle to the car, and then pick up the bow and swing it around and put it up on the car rack. I then pick up the stern and shove the yak forward. No problem at all. I put my yak on the rack bottom side down. It slides on the bottom much better than on the gunwales. Hobie says to carry on a rack upside down, but I put two "rails" made of 1" PVC covered with polyethylene pipe insulation and 6' long under the yak. They fit in the bottom grooves and lift & support (just like a Playtex bra
) the yak so it doesn't touch the rack. I figure this distributes the weight well enough to keep deformation from being a problem. Time will tell, I guess.