I have purchased 2011 Hobie Mirage Oasis Tandem and have had a horrible experience with it.
I volunteered as a safety kayaker to support the 7.5 mi. Potomac swim on 6/4/2011 (http://artemis.crosslink.net/~cherylw/pr2007i.htm
It was windy and a bit rough, but I was unable to control my kayak at all, even with the rudder and mirage drives installed. It had no tracking (st)ability, what so ever! I was paddling sideways, making circles and loops. I was unable to control my kayak at all, both peddling and paddling! With the rudder all the way, it would just not turn right! I was shamefully taken out of the race and barely made it to shore, on my own. It was like trying to paddle a washtub! The bottom of the kayak is round and there is no keel to speak of, to assist in tracking / keeping the course. I am an experienced kayaker and am extremely frustrated / disappointed, after spending thousands of dollars on the kayak and accessories for this model, I would not recommend to anyone. It is a safety hazard and should be taken off the market!