After several years lurking here, I finally bought an AI Classic; an early 2010 model manufactured late in '09. I've already bought my first accessory, too - an inflatable SUP to use as an haka:
It packs down in that gray duffel, and, as you can see, a SUP paddle fits in the paddle holder better than a kayak paddle. (It looks like the mold was designed for a plain Adventure and the addition of the akas interferes slightly with the paddle shaft.)
When pedaling or sailing from the vaka, it makes a nice rest to lean against.
I thought I would have to get a frame underneath to keep it from sagging, but was pleasantly surprised to find that it's stiff enough to stand on and paddle with no issues. Didn't have a selfie stick long enough to get a shot of that! It was light wind today, so I can't comment on how much air it catches, but I'm guessing a lot.
I'm going to experiment with setting a tarp up over it as a sleeping platform, and if you had to moor offshore, you could even use it as a tender!