A friend of mine has a Can-Am which chronically was going into limp mode. Trust me, you don't want to be out in the middle of nowhere and have to escort your friend who can only go about 25 mph.
The dealer was worthless, no help, no ideas. We finally figured out that if he used premium gas without alcohol it ran fine. Apparently the knock sensor was tripping the limp mode due to the crummy alcohol laced premium we have available here. Bottom line is that you better not go any further than that good tank of fuel will get you.
The weave, high center, vague steering was adjusted out by extensive tinkering with the suspension settings and tire pressures. No science was involved, just trial and error, recording everything so the settings could be reproduced/tweaked.
From what I have seen myself, even though the Can-Am appears very highly engineered and looks to have much going for it, I would would not want one. I have friends with Honda trikes and am unaware of any issues with any of them.