When I use the "Put Right" function of the Compiz grid plugin to maximize a window on the right half of a desktop, a two-pixel stripe of the window ends up on the next virtual desktop just to the right. The window then appears on two desktops simultaneously, which is a bit inconvenient to handle. "Put Left" works fine, interestingly.
I run 11.10 with unity. Any idea if that is a known bug?